So I’ve had high phosphates due to a faulty Red Sea test kit and now with a Hanna phosphorus checker I’ve been testing daily and changing rowaphos as it starts to go up and can keep It bewtween 12-20ppb. My nitrates have always been really low I use Red Sea and have had my lfs test and it’s below 1 it’s clear looking thru the top but there’s the faintest shade of pink when I look thru the side. I was wondering if increasing my nitrates would be healthier for the tank and I’ve been reading it could help with phosphates lowering
Will increasing nitrates help
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Colin_S
Active Member
I try and keep nitrate between 5-15ppm. I believe that it will keep algae at bay and corals feed of it.
Do you have many corals?
What size is your tank?
What filtration do you use to deal with nitrate and phosphate?
How does your tank look? if it looks good I would keep it stable.
Don't zero out nitrate & phosphate, you may get algae.
I don't believe increasing your No3 will reduce your Po4, more likely the opposite.
There' a ratio of when REDUCING No3, that Po4 will reduce at a ratio of 1-12, something like that. So if thats the case I would imagine Rising No3 will rise Po4 slightly. You might not even notice it.
Do you have many corals?
What size is your tank?
What filtration do you use to deal with nitrate and phosphate?
How does your tank look? if it looks good I would keep it stable.
Don't zero out nitrate & phosphate, you may get algae.
I don't believe increasing your No3 will reduce your Po4, more likely the opposite.
There' a ratio of when REDUCING No3, that Po4 will reduce at a ratio of 1-12, something like that. So if thats the case I would imagine Rising No3 will rise Po4 slightly. You might not even notice it.
Yes, in a nitrate limited system, the addition of nitrates will lower PO4. The bacteria that consume/process PO4 are nitrate limited.
IMO, your phosphate levels are already good -- .037 to .061 is considered an ideal residual level. There is an error margin +-.02 and bumping zero is a really bad thing unless your are feeding several times per day.
IMO, your phosphate levels are already good -- .037 to .061 is considered an ideal residual level. There is an error margin +-.02 and bumping zero is a really bad thing unless your are feeding several times per day.
Dkmoo
Valuable Member
Algae absorbs N to P at about 20:1
Increasing No3 will help reduce po4 in situations where your no3 is so low that its prohibiting algaes from uptaking P.
All organisms absorb N and P in fixed ratios (some high some low) but the absence of either will limit the absorption of the other. Not all organisms absorb them in the form of no3 and po4 either. Diatoms and bacteria uptakes P qt a higher ratio than algae thats why high po4 often results in diatom and cyano blooms.
If you have healthy algae growth, ie, from a fuge, and very low no3 levels, then adding N will help unlock po4 absorption by algae.
Increasing No3 will help reduce po4 in situations where your no3 is so low that its prohibiting algaes from uptaking P.
All organisms absorb N and P in fixed ratios (some high some low) but the absence of either will limit the absorption of the other. Not all organisms absorb them in the form of no3 and po4 either. Diatoms and bacteria uptakes P qt a higher ratio than algae thats why high po4 often results in diatom and cyano blooms.
If you have healthy algae growth, ie, from a fuge, and very low no3 levels, then adding N will help unlock po4 absorption by algae.
Ye I have fuge and recently upgraded the light to the ai fuge light and it’s now growing rapidly. I don’t have any nuisance algae in the tank just starting to get coralline grow tank is approx 8 months old started with dry rock and sand. Phosphates is sitting in range but that’s due to everyday testing and constantly replacing rowaphos I only use 3 tea spoons a time to make sure it never bottoms out I was just wondering if dosing nitrates can help with the uptake of phosphate thanks for answering that. Is there a specific product you would recommend and a certain number to be at would raising to 5 be a good place to aim for
I tested today and it was basically undetectable when I looked thru the top it was completely clear looking thru the side there was the slightest hint of pink so I’d say below 1 I use Red Sea test kit not the pro one tho
Dkmoo
Valuable Member
Some sodium nitrate could help. However, before going that route please consider the following.
1) 8 month is common time for po4 problem to pop up. This is part of the "young tank syndrome" because of the lack of biodiversity - a lot of the stuff that add to biodiversity, such as pods, different hitchhiker cuc like worms, and stable bacteria population, are very effective P absorbers. So, the only true long term solution is time and tank maturity
2) the primary nutrient absorbers in young tanks are more N absorbers like corals and algae. This imbalance is also related to what you have been feeding. New rocks and sand also tend to absorb P until saturation then start leaching back out. This often happens are the 8 month mark.
3) rowephos is effective at absorbing po4, but it doesn't really help your tank mature in the long term. Meaning, if you depend your primary po4 export on external media + algae, then you are really never giving the "heavy P eaters" part of your microfauna a chance to establish. So this means you will always depend on rowphos and algae, and a problem in either will cause your po4 to come back.
4) consider what you are feeding? Meaty stuff have higher P, if the N to P ratio of what you feed doesn't match your uptake, the imbalance will persist. If you have corals, dosing amino will actually be better than dosing no3 directly bc amino is all N and no P. Dosing sodium no3 will only really help algae absorbing n and p, and will benefit corals to a smaller degree only in its beneficial effect to the zoox.
1) 8 month is common time for po4 problem to pop up. This is part of the "young tank syndrome" because of the lack of biodiversity - a lot of the stuff that add to biodiversity, such as pods, different hitchhiker cuc like worms, and stable bacteria population, are very effective P absorbers. So, the only true long term solution is time and tank maturity
2) the primary nutrient absorbers in young tanks are more N absorbers like corals and algae. This imbalance is also related to what you have been feeding. New rocks and sand also tend to absorb P until saturation then start leaching back out. This often happens are the 8 month mark.
3) rowephos is effective at absorbing po4, but it doesn't really help your tank mature in the long term. Meaning, if you depend your primary po4 export on external media + algae, then you are really never giving the "heavy P eaters" part of your microfauna a chance to establish. So this means you will always depend on rowphos and algae, and a problem in either will cause your po4 to come back.
4) consider what you are feeding? Meaty stuff have higher P, if the N to P ratio of what you feed doesn't match your uptake, the imbalance will persist. If you have corals, dosing amino will actually be better than dosing no3 directly bc amino is all N and no P. Dosing sodium no3 will only really help algae absorbing n and p, and will benefit corals to a smaller degree only in its beneficial effect to the zoox.
Excellent point. I often think of this only in terms of bacteria, but the same applies to algae -- even more so if you are running a fuge or scrubber.
Well said. This is wisdom. All heed.
Timfish
Crusty Old Salt
Feed your fish more. Corals prefer organic nitrogen in the forms of amino acids and urea and the inorgainc ammonia/ammonium over nitrates. Corals also have simbiontic diazotrophs in their holobiont to fix nitrogen. Nitrate is their least faovorite form of nitrogen. Also keep in mind particualte and orgainc forms of phosphorus. Here's some links if you're interested:
mmonium Uptake by Symbiotic and Aposymbiotic Reef Corals
www.ingentaconnect.com
www.cambridge.org
An Experimental Mesocosm for Longterm Studies of Reef Corals
Phosphate Deficiency:
Nutrient enrichment can increase the susceptibility of reef corals to bleaching:
www.nature.com
Ultrastructural Biomarkers in Symbiotic Algae Reflect the Availability of Dissolved Inorganic Nutrients and Particulate Food to the Reef Coral Holobiont:
www.frontiersin.org
Phosphate deficiency promotes coral bleaching and is reflected by the ultrastructure of symbiotic dinoflagellates
www.sciencedirect.com
Effects of phosphate on growth and skeletal density in the scleractinian coral Acropora muricata: A controlled experimental approach
www.sciencedirect.com
High phosphate uptake requirements of the scleractinian coral Stylophora pistillata
jeb.biologists.org
Phosphorus metabolism of reef organisms with algal symbionts
Sponge symbionts and the marine P cycle
www.pnas.org
Phosphorus sequestration in the form of polyphosphate by microbial symbionts in marine sponges
www.pnas.org
Sugar enrichment provides evidence for a role of nitrogen fixation in coral bleaching
onlinelibrary.wiley.com
Nitrogen cycling in hte coral holobiont
mmonium Uptake by Symbiotic and Aposymbiotic Reef Corals
Ammonium Uptake by Symbiotic and Aposymbiotic Reef Corals: Ingenta Connect
An experimental mesocosm for long-term studies of reef corals | Journal of the Marine Biological Association of the United Kingdom | Cambridge Core
An experimental mesocosm for long-term studies of reef corals - Volume 92 Issue 4
Phosphate Deficiency:
Nutrient enrichment can increase the susceptibility of reef corals to bleaching:
Nutrient enrichment can increase the susceptibility of reef corals to bleaching - Nature Climate Change
Increased dissolved inorganic nitrogen (DIN) concentrations in sea water have been linked to a reduction of the temperature threshold at which corals bleach, however, the mechanism underlying this change is not known. This phenomenon is now explained in terms of increased phosphatase activities...
www.nature.com
Ultrastructural Biomarkers in Symbiotic Algae Reflect the Availability of Dissolved Inorganic Nutrients and Particulate Food to the Reef Coral Holobiont:
Frontiers | Ultrastructural Biomarkers in Symbiotic Algae Reflect the Availability of Dissolved Inorganic Nutrients and Particulate Food to the Reef Coral Holobiont
Reef building corals associated with symbiotic algae (zooxanthellae) can access environmental nutrients from different sources, most significantly via the up...
www.frontiersin.org
Phosphate deficiency promotes coral bleaching and is reflected by the ultrastructure of symbiotic dinoflagellates
Phosphate deficiency promotes coral bleaching and is reflected by the ultrastructure of symbiotic dinoflagellates
Enrichment of reef environments with dissolved inorganic nutrients is considered a major threat to the survival of corals living in symbiosis with din…
Effects of phosphate on growth and skeletal density in the scleractinian coral Acropora muricata: A controlled experimental approach
Effects of phosphate on growth and skeletal density in the scleractinian coral Acropora muricata: A controlled experimental approach
Phosphate contamination can negatively affect corals, modifying growth rates, skeletal density, reproduction, mortality, and zooxanthellae. We determi…
High phosphate uptake requirements of the scleractinian coral Stylophora pistillata
High phosphate uptake requirements of the scleractinian coral Stylophora pistillata
SUMMARYSeveral untested aspects of the regulation of inorganic nutrient uptake were examined using nutrient depletion experiments with the symbiotic coral Stylophora pistillata. The total inhibition of phosphate uptake in artificial seawater lacking sodium indicates the involvement of a...
jeb.biologists.org
Phosphorus metabolism of reef organisms with algal symbionts
2657円まるいち 博多辛子明太子(無着色) 「博多の華」 (ギフト用) 180g Z6572海産物イクラ,タラコ,魚卵 Qoo10] 「博 まるいち 博多辛子明太子(無着色) | therichross.com
2657円まるいち 博多辛子明太子(無着色) 「博多の華」 (ギフト用) 180g Z6572海産物イクラ,タラコ,魚卵 Qoo10] 「博 まるいち 博多辛子明太子(無着色) | therichross.com
therichross.com
Sponge symbionts and the marine P cycle
Sponge symbionts and the marine P cycle
Marine sponges are ubiquitous colonizers of shallow, clear-water environments in the oceans (1, 2). Sponges have emerged as significant mediators of biogeochemical fluxes in coastal zones by virtue of respiring organic matter and facilitating both the consumption and release of nutrients (3, 4)...
Phosphorus sequestration in the form of polyphosphate by microbial symbionts in marine sponges
Phosphorus sequestration in the form of polyphosphate by microbial symbionts in marine sponges
Coral reefs are highly productive ecosystems that raise a conundrum called “Darwin’s paradox”: How can high production flourish in low-nutrient conditions? We show here that in three abundant Caribbean sponges, the granules that have been commonly observed in sponge tissue for decades are...
Sugar enrichment provides evidence for a role of nitrogen fixation in coral bleaching
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Nitrogen cycling in hte coral holobiont
Really interesting info. Thanks for sharing. My tank has been up and running for three years with elevated phosphates (.15-.20) for some time. I'd like to believe my tank is mature, but about a year and a half ago I changed my lighting schedule to run at peak for 4-5 hours and in doing so I caused the uglies to come out.
This never really happened when I first set the tank up as my lights simply weren't powerful enough. I'm thinking this is because my lights were ramped up and ramped down running at high intensity for maybe an hour. I made this change as I began to start adding acros to the tank.
During this ugly phase I lost a lot of coral, battled algae of all kinds and my arch nemesis, cyano. I ended up dosing chemiclean to eliminate the cyano, which eventually made its way back. I've now been battling it for several months and am my wits end.
As this relates to this thread, I began dosing nitrates as they were untraceable thinking it would help to reduce the phosphates.. it didn't work. My nitrates are currently around 10 with my phosphates around .12, but I know the actual numbers are significantly higher. I did a three day blackout period to knock back the cyano and following the blackout my phosphates registered nearly twice as high around .21 and my nitrates were unchanged.
At this point, I'm running out of ideas and am thinking about trying the following:
1)a) dose chemiclean
b) add live sand to replinish beneficial bacterias I may lose and add additional surface area for added filtration
c) run gfo or dose phosphate-e to reduce and maintain phosphate levels
d) dose microbacter7 and microbacter clean to add/replenish bacterias
e) add several types of pods
I know it's a lot, but don't know what else I can do. Should I be concerned about cycling my tank/sand? I've tried dosing nitrates to reduce phosphates, dosing microbacter 7 and running an algae reactor to no avail.
Should I be trying something else? Perhaps just the gfo/phosphate-e first?
Any thoughts or recommendations you could provide would be greatly appreciated.
Dkmoo
Valuable Member
wow that is quite a lot.
there is definitely a phosphate battery in your tank somewhere, and right now its mainly absorbed by cyano - makes sense that when you blacked out, the cyano stopped absorbing, so po4 raised. maybe when your light was subdued in the first 1.5 years, the imbalance has been charging the P battery all along and that's taking a while now to discharge (esp if your are still bringing more P in when you feed). what have you been feeding? want to make sure that's not a high source of P replenishment.
chemiclean kills cyano but doesn't help your high P problem - it doesn't remove the cyano from your system so the dead cyano just releases P back to your water and in fact you have killed the most efficient P absorber currently in your system.
how has your sand been? is there a ton of worms that's actively flipping the sand. If your've never flipped the sand and not a lot of natural turnover, it could be the stratified layers of waste thats leaching po4 back up (full diaper effect). If you haven't stirred your sand in 3 years, don't do it now. may crash your system with the sudden release of waste. instead do deep vacuums over a small section every time your do WC.
do you have fuge? point of dosing N is to make algae grow and take the P with it.
biodiversity is something thats best achieved naturally - b/c the interactions are soo complex that it's really hard to figure out what exactly you need and what effect it'll have - so like "dosing bacteria" or "dosing pods" may not give you the result you hope for - ie, if pods dont have the right food, they'll just die and release more N and P.
for now, i would just stick to one method of removal while minding what you are putting back in. it's going to take a while to see results but as long as what you take out is more than what you put it, eventually the battery will be exhausted. I'd go with fuge personally but GFO will be a quicker short term result. once you get the situation under control and exhaust the P battery, you can then think about slowly transitioning out of GFO into more natural P control methods. Don't view cyano as this bad thing for your tank that you have to kill with some chemical - think of it as a P cleaner - the more it grows (and you can syphon out) the more P you are removing from the tank.
key is to stick to one and keep it up - it takes months to truly see the impact of any method as your tank adjusts and reequalizes.
GL!
there is definitely a phosphate battery in your tank somewhere, and right now its mainly absorbed by cyano - makes sense that when you blacked out, the cyano stopped absorbing, so po4 raised. maybe when your light was subdued in the first 1.5 years, the imbalance has been charging the P battery all along and that's taking a while now to discharge (esp if your are still bringing more P in when you feed). what have you been feeding? want to make sure that's not a high source of P replenishment.
chemiclean kills cyano but doesn't help your high P problem - it doesn't remove the cyano from your system so the dead cyano just releases P back to your water and in fact you have killed the most efficient P absorber currently in your system.
how has your sand been? is there a ton of worms that's actively flipping the sand. If your've never flipped the sand and not a lot of natural turnover, it could be the stratified layers of waste thats leaching po4 back up (full diaper effect). If you haven't stirred your sand in 3 years, don't do it now. may crash your system with the sudden release of waste. instead do deep vacuums over a small section every time your do WC.
do you have fuge? point of dosing N is to make algae grow and take the P with it.
biodiversity is something thats best achieved naturally - b/c the interactions are soo complex that it's really hard to figure out what exactly you need and what effect it'll have - so like "dosing bacteria" or "dosing pods" may not give you the result you hope for - ie, if pods dont have the right food, they'll just die and release more N and P.
for now, i would just stick to one method of removal while minding what you are putting back in. it's going to take a while to see results but as long as what you take out is more than what you put it, eventually the battery will be exhausted. I'd go with fuge personally but GFO will be a quicker short term result. once you get the situation under control and exhaust the P battery, you can then think about slowly transitioning out of GFO into more natural P control methods. Don't view cyano as this bad thing for your tank that you have to kill with some chemical - think of it as a P cleaner - the more it grows (and you can syphon out) the more P you are removing from the tank.
key is to stick to one and keep it up - it takes months to truly see the impact of any method as your tank adjusts and reequalizes.
GL!
The reason that it can take a while for P to start to show is that the fresh sand and rock (if not already bound up with terrestrial phosphate) will bind it for a while until levels start to rise. It is smart to study up on phosphate binding to aragonite and the relationship between the two - it is complex but good to know to help you with your hobby experience. Some who start the tank with dry/dead rock have high phosphate from the beginning since they have it all bound up in the source - this can take a while to leave the tank and get lower, if it ever does.
Nitrate is not great for your corals, but macro algae can use it directly. Ammonia/ammonium is better for nitrogen as is catching bacteria (if they can) and assimilating things through the slime coat. As said above, just feed the fish heavy and also export heavy on the back end (skim a lot, fuge, etc.). Availability is the prize, not residual levels on a test kit.
The same is somewhat true with P. Phosphorous/Phosphate/organic/inorganic can be used in different forms, but you test for only one and add only one if you dose. Just let the fish excrete the different kinds of P naturally after they eat the foods.
Do your homework and study up on the biology. Nitrate is not food. It does not offer energy. It is a building block. Every living thing needs some to build new organic tissue, but having more than needed does not do anything extra. Most corals (hosts) can recycle building blocks for their symbionts to use for tissue repair, so N is only needed mostly for new growth... this is not likely to continue forever and there are some caveats, but for the most part, lack of nitrate does not cause death in the short term, just slowed growth if truly limited. Unless you are using media, chemicals or organic carbon, it is hard to be growth limited with nitrogen.
Nitrate is not great for your corals, but macro algae can use it directly. Ammonia/ammonium is better for nitrogen as is catching bacteria (if they can) and assimilating things through the slime coat. As said above, just feed the fish heavy and also export heavy on the back end (skim a lot, fuge, etc.). Availability is the prize, not residual levels on a test kit.
The same is somewhat true with P. Phosphorous/Phosphate/organic/inorganic can be used in different forms, but you test for only one and add only one if you dose. Just let the fish excrete the different kinds of P naturally after they eat the foods.
Do your homework and study up on the biology. Nitrate is not food. It does not offer energy. It is a building block. Every living thing needs some to build new organic tissue, but having more than needed does not do anything extra. Most corals (hosts) can recycle building blocks for their symbionts to use for tissue repair, so N is only needed mostly for new growth... this is not likely to continue forever and there are some caveats, but for the most part, lack of nitrate does not cause death in the short term, just slowed growth if truly limited. Unless you are using media, chemicals or organic carbon, it is hard to be growth limited with nitrogen.
Really appreciate the quick feedback. I don't have a fuge, but am running an algae reactor with chaeto, so same I guess. My sand bed has been okay, but I've slowly removed it (accidentally) through water changes and vacuuming. I haven't found a way to remove the cyano without removing top layer of sand yet no matter what I try. This is why Im considering adding the live sand. I have a bunch of dry sand, but think that would be a bad idea. I do have a sand sifting star, several nessarius snails and had a conche that recently died.. thinking he starved or the cyano killed him.
For food I'm feeding one to two cubes of mysis I thaw and strain before dropping in. I also feed sea veggies for the tangs every other day and will drop in some seaweed extreme pellets from time to time. I fed the seaweed extreme pellets daily and heavily for a while and think this may be what ultimately got me here, but who knows. I'm just guessing at this point.
I'm thinking about going the gfo route, but am concerned about my phosphates bottoming out.. definitely don't want dinos. If I use gfo to get the phosphates down, but not entirely zeroed out won't the cyano continue to grow unless it's zero?
This is why I was considering dosing the chemiclean, then immediately adding the gfo to get the phosphates out/down and add the sand/bacteria to replace what if any was lost.
This is great info as well. I've read up quite a bit on this, but still struggle to understand a lot of it.. I've read that dosing amino acids may be the best alternative to dosing nitrates other than more feeding. Would you agree with that?
Dkmoo
Valuable Member
How big and how much is the chaeto growing? chaeto needs to reach a critical mass to be able to effectively outcomepete the nutrient in the water that's currently being competed by the stuff in your DT that has the fancy lights and more volume. Also got a skimmer? as mentioned above - up the export game on the back end.
This is charging the P battery too, for sure
mysis got pretty high P, not just in the juice
cyano will always be in your system. A mature tank with diverse microfauna will keep it in check via competition. i'm not just referring to PO4 that cyano absorbs - i'm talking about all forms of P - from food particles, dissolved organics, etc. ie, worms will eat up any remaining food that falls to the sand, feather dusters/vermetid snails will help catch dissolved organics in the water, etc.. this is what takes time to stablish. if your star has been in your system for a while it may actually be the reason for your lack of biodiversity in the sand - it probably ate all the pods/worms in there and your sand was not mature enough to support one.
IMHO trying to "time" the different reactions in a multi-step sequences may not work out as you'd hope for. The biochemical process that's happening in our tank is so complex and interconnected, and it's never happens in the sequential order that you envision - ie, it's not like day 1 - day 3, cyano will eat the P, then day 4 chemiclean will come in and kill all the cyano, then day 5 gfo comes on and takes out all the cyano. What's really happening in the tank is a lot more messy and random (plus interactions we havent even thought of).
I'd just first try to cut back on mysis, keep up with syphoning the cyano (since that's still a very efficient way of physically removing P from your system) - those cyano carpets are real little P sponges, and let your chaeto grow out more (if it's small), and see where you are in a couple of months.
I appreciate you bud! I have the reef octopus LR 200 reactor and nyos 160 skimmer. I probably harvest the chaeto too often and will let it grow out more going forward.
For added background, my tank is 160 gallons roughly with about 100/125 pounds of fiji live rock and an inch or so of carib sea sand. I have three clowns, five tangs (three small, two medium/large) one coral beauty, two anthias, one tiny watchman goby and a royal grama. I have a small cleanup crew, two emerald crabs, one peppermint shrimp, pistol shrimp, urchin, 3-4 banded trochus snails, 5 hermits assorted, sea star, one dying turbo and 4-5 nassarius snails. I'm pretty heavily stocked with coral of all kinds so a mixed reef tank. I'm thinking part of my problem is I may need more filtration/surface area for the bacterias. I had a real good pod population that got wiped out with the ugly phase/cycle I mentioned earlier and am seeing them starting to slowly make a comeback.
Not sure I follow what you say is charging the p battery? I did add dry sand and dry rock, but I cured the live rock for two months and rinsed the hell out of the rock and sand before getting it in the tank, and that was over three years ago.
Regarding the food, I actually recently switched to feeding more mysis as I added the anthias, goby and grama that love the mysis.. pretty much all they eat. All my other fish love the seaweed pellets. Is there an alternative these guys will eat that you recommend?
I do understand what you're saying and will be changing my strategy.
I will grow the chaeto out and harvest less, cut back feeding the mysis and find an alternative (open to suggestions). I will syphon out the cyano on my next water change and add the gfo to help get the phosphate down. Do you think adding some live sand would hurt? Maybe a brightwell bio block?
Apologies for all the questions. As you can see I'm super OCD about this. It's driving me absolutely nuts to have such a nice piece of living art with a bunch of nasty red/brown crap all over the tank slowly killing things.
I really appreciate you taking the time to help me and provide guidance. Thanks again!
Dkmoo
Valuable Member
so the P battery i'm talking about is basically the accumulation of organic waste since when you first started the tank. the waste that's in the pores of the rocks, the P binding mechanism that's mentioned by other posters above. so in theory, perhaps every time you fed something, you put more P in than your animals can absorb, and the extra waste gets bound in the substrate and stored in the rock pores. this accumulates little by little, creating stores of P in the rock and sand. then every time something dies, if you don't quickly take it out, the dead flesh rots and get buried in the sand, thus increasing the storage of P (charging the battery).
for feeding fish - give them a variety - you can still feed mysis but rotate it with something else that's more plant/plankton based.
dose amino for your corals if you got a lot - but probably not necessary since your fish pee/poop is already good for corals - and you got a lot of fish.
live sand doesn't hurt. I never used bioblock so not sure about that product. But it still feels like you are trying to do too much too quickly - here you suggested doing 5 things - add sand, reduce feed, increasing filtration (chaeto mass), add bio block, add gfo. i get you want to fix it asap but for a tank that big, it truly takes months for any one little adjustment you make to show its full effect. doing too many things too quickly doesn't make your tank stablize faster and oftentimes has the opposite effect b/c we really don't fully understand all the intricate biochemical process and relationships our tank has. The closest analogy i can make is - you are trying to untangle a ball of yarn that has multiple open threads - pulling at one thread tip is gonna be slow to untangle, but at least you'll be able trace thru the thread. Pulling at all of them at the same time MIGHT make you untangle faster, but more likely will make the yarn knot even tighter.
That's why i suggested only changing feeding and letting chaeto grow out for couple of months. If you go the GFO route then that would be the only change I would do now, b/c gfos can strip out P so effectively that i'd want to monitor and keep everything else status quo for now.
for feeding fish - give them a variety - you can still feed mysis but rotate it with something else that's more plant/plankton based.
dose amino for your corals if you got a lot - but probably not necessary since your fish pee/poop is already good for corals - and you got a lot of fish.
live sand doesn't hurt. I never used bioblock so not sure about that product. But it still feels like you are trying to do too much too quickly - here you suggested doing 5 things - add sand, reduce feed, increasing filtration (chaeto mass), add bio block, add gfo. i get you want to fix it asap but for a tank that big, it truly takes months for any one little adjustment you make to show its full effect. doing too many things too quickly doesn't make your tank stablize faster and oftentimes has the opposite effect b/c we really don't fully understand all the intricate biochemical process and relationships our tank has. The closest analogy i can make is - you are trying to untangle a ball of yarn that has multiple open threads - pulling at one thread tip is gonna be slow to untangle, but at least you'll be able trace thru the thread. Pulling at all of them at the same time MIGHT make you untangle faster, but more likely will make the yarn knot even tighter.
That's why i suggested only changing feeding and letting chaeto grow out for couple of months. If you go the GFO route then that would be the only change I would do now, b/c gfos can strip out P so effectively that i'd want to monitor and keep everything else status quo for now.
