Dosing Phosphates, but not nitrates?

@justd1
here is the thread i pulled my inital calc from.
it'll point you in the right direction. shoot me a msg if you have any questions.

Thank you! I greatly appreciate it!
 
Hey everyone,

I have a 45 gallon mixed reef. Softie and LPS dominant with a couple SPS. I have a good handle on my nitrates. They are stable around 5-10ppm. My Phosphates always read 0. I have dosed a small amount of PO4 before and was able to increase it to .03-.06. That only lasts about a day before my tank uses it all and it's back to 0. Should I continue to dose PO4 in these small amounts everyday? Does anyone know why my tank would be using so much PO4, but not Nitrates? Everything in my tank looks good and I'm happy. I'm just worried of my PO4 bottoming out. I do know even though my test kits read 0 there are still probably some PO4 in the tank.
I am having same problem! if I knew this would happen after dosing nopox I never would have. My nitrates shot up to 80 after adding and feeding a bunch of frags. To much bioload at once. My phos stayed low at 0 or 0.1 or something because i always used gfo. Now no matter what I do I cant get phos up. I have dosed neophos 3 times and nothing and overfeeding corals and nitrates stay at2 or 3. I have some type of algae problem now and dont know what it is because its not string like dinos or red and slimy like cyano. Looks like diatoms on sand but heavily coated the back glass and wavemakers, Some on front glass to and rocks. I just hope I dont have to dose forever and wonder if I should dose nitrtes even though I am fine with them at 2 or 3. I have been dosing MB& and vibrant as well and got all algae off except GHA. Its does look better but kind of scared to do a waterchange because thats when it got real bad!
 
I've had 'undectable' PO4 for 12+ years, so this can become a permanent thing. This may, or may not, be an issue and here's why.

There is a big difference between phosphate being continually utilized in a system (but showing PO4 '0' in the water column on a test kit) and a true PO4 '0' condition. It's the difference between a system that's fed often (phosphate being added regularly) and one where phosphate input (feeding, mostly) is sparse to non-existent. In the former case, nothing to worry about, usually, but in the later case possibly dinos and pale/weakened/starving corals. Also to consider, regular feeding adds both inorganic phosphate (aka 'orthophosphate' or 'PO4') and multiple organic phosphate forms (not tested for with typical hobbyist test kits).

In addition to testing, old salts will tell you to 'look at the corals' as they are the visible indicators that will show you if they are getting enough nutrients', or not. If my corals are plump/expanded and nicely colored up with a constant '0' PO4 reading, then it's all good as far as I'm concerned. If they start to shrivel, loose color or worse (and all parameters are within reef keeping norms), then time to increase nutrients.

The question of why some systems are so effective at processing PO4 and so many are not is a very interesting one. Even very similarly run systems can have quite different nutrient processing capabilities. I don't believe that there is a simple answer to this question (or else someone would have come up with it by now).
 
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I’ve been through this and I feel like a majority of tanks run into This problem. I have to dose 250ml of neophos into my 5 gallon ato container to maintain detectable p04 and I also dose 15ml of me coral n03 everyday in my reefer 450. Jack Kent gave me a 2 gallon jug of neophos and as soon as I’m done with it I’m going back to my trisodium phosphate mixture. My tank is also packed with acros which are sponges for nutrients. There are far more advantages to having high nutrients than low imo. I shoot for 10ppm n03 and .06 p04. If I stop dosing either nutrient I can see my acros aren’t happy and start to lose color. Keep in mind I don’t have a refugium, no algae scrubber, no Carbon dosing, no gfo or GAC, and I only run my skimmer for an hour every 3 days (cone s 2). The more sps you have the more nutrients they need. Hope this helps. Thanks Garrett
I thought sps was the oposite, that they liked less nutrients!
 
I've had 'undectable' PO4 for 12+ years, so this can become a permanent thing. This may, or may not, be an issue and here's why.

There is a big difference between phosphate being continually utilized in a system (but showing PO4 '0' in the water column on a test kit) and a true PO4 '0' condition. It's the difference between a system that's fed often (phosphate being added regularly) and one where phosphate input (feeding, mostly) is sparse to non-existent. In the former case, nothing to worry about, usually, but in the later case possibly dinos and pale/weakened/starving corals. Also to consider, regular feeding adds both inorganic phosphate (aka 'orthophosphate' or 'PO4') and multiple organic phosphate forms (not tested for with typical hobbyist test kits).

In addition to testing, old salts will tell you to 'look at the corals' as they are the visible indicators that will show you if they are getting enough nutrients', or not. If my corals are plump/expanded and nicely colored up with a constant '0' PO4 reading, then it's all good as far as I'm concerned. If they start to shrivel, loose color or worse (and all parameters are within reef keeping norms), then time to increase nutrients.

The question of why some systems are so effective at processing PO4 and so many are not is a very interesting one. Even very similarly run systems can have quite different nutrient processing capabilities. I don't believe that there is a simple answer to this question (or else someone would have come up with it by now).
The problem with the 0 phospates Is I am pretty sure I have dino from it being 0. My corals look fine and I was feeding them nightly trying to up nitrates but now thatit is 3 I am going back to feeding 2 x's a week. I only have 2 fish so not much fish food going on but they do tend to miss a lot of pieces that hit the sand...lol

Hvae you ever had dinos from 0 phos? I read that is the perfect breeding ground for it but mine looks more like diatoms but after waterchange it gets reall heavy on glass sand rocks ect.. I am having to do WC though because my alk has been dropping since I added t o many corals at one and its dropping very inconsistently so I cant really dial in a dose to start adding 2 part. Thats how I got in this situation was adding the corals and upped my nitrates to 80 so I started nopox for a few weeks I guess and bottom nutrients out!

Bad move. If I would have realized I could get dinos I would have just did a bunch of waterchanges!
 
the way i understood it is that the rock will absorb po4 up to the concentration that the water is, but not more. then when the water is lower concentration it will release it to maintain it.

what rock will not do, is absorb phosphate until it is "full" then stop. (unless po4 concentrations are maintained super high for a long period of time)

so:
if you keep your po4 at 1ppm, the rock will absorb until it is also 1ppm, then when your po4 drops to .5ppm the rock will release it until it is balanced back out.


** this is how in understand it, i'm far from an expert on this**

@Randy Holmes-Farley @Lasse

This is my understanding as well. After dinos stripped all PO4 from my system, it took two liters of DIY PO4 to load the rock back up to that point where PO4 was measurable in the water.
 
Hvae you ever had dinos from 0 phos? I read that is the perfect breeding ground for it but mine looks more like diatoms but after waterchange it gets reall heavy on glass sand rocks ect.. I am having to do WC though because my alk has been dropping since I added t o many corals at one and its dropping very inconsistently so I cant really dial in a dose to start adding 2 part. Thats how I got in this situation was adding the corals and upped my nitrates to 80 so I started nopox for a few weeks I guess and bottom nutrients out!

Bad move. If I would have realized I could get dinos I would have just did a bunch of waterchanges!

No, I have never had dinos. I have had a coca-cola colored organism (likely a type of cyano) cover the sand bed and a few nearby rocks for up to 9 months at a time. I believe that the cause was related to too much feeding (too many fish) with the excess nutrients building up in the rocks and sand bed, fueling the organism's growth. Lowering the fish load along with regular detritus removal eventually eliminated the bloom after a few months time.

My advice to anyone with low PO4 in the system is to go slow and be very careful/conservative with carbon dosing (vinegar, vodka, NOPOX, etc.). While carbon dosing is mainly used to reduce nitrate, it also reduces phosphate (but at a slower rate). If a system is already reading '0' PO4, then the additional phosphate reduction has the very real potential to cause issues.

It would perhaps be safer to first raise PO4 (especially newer systems) to at least detectable levels before starting any form of carbon dosing, IMO.
 
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The problem with the 0 phospates Is I am pretty sure I have dino from it being 0. My corals look fine and I was feeding them nightly trying to up nitrates but now thatit is 3 I am going back to feeding 2 x's a week. I only have 2 fish so not much fish food going on but they do tend to miss a lot of pieces that hit the sand...lol

Hvae you ever had dinos from 0 phos? I read that is the perfect breeding ground for it but mine looks more like diatoms but after waterchange it gets reall heavy on glass sand rocks ect.. I am having to do WC though because my alk has been dropping since I added t o many corals at one and its dropping very inconsistently so I cant really dial in a dose to start adding 2 part. Thats how I got in this situation was adding the corals and upped my nitrates to 80 so I started nopox for a few weeks I guess and bottom nutrients out!

Bad move. If I would have realized I could get dinos I would have just did a bunch of waterchanges!
 
This is my understanding as well. After dinos stripped all PO4 from my system, it took two liters of DIY PO4 to load the rock back up to that point where PO4 was measurable in the water.
Did it every measure soon after you added it? I checked today a few hours later and it detected phos but by the nextday when I usually check it is when its undectable. I dint realize that dinos spripped po4. Pretty sure that what I am dealing with. But my phos was 0 before dinos from carbon dosing and b4 that I used GFO, so it was already low perhaps zero even. I cant remember and cant find my logs.
 
No, I have never had dinos. I have had a coca-cola colored organism (likely a type of cyano) cover the sand bed and a few nearby rocks for up to 9 months at a time. I believe that the cause was related to too much feeding (too many fish) with the excess nutrients building up in the rocks and sand bed, fueling the organism's growth. Lowering the fish load along with regular detritus removal eventually eliminated the bloom after a few months time.

My advice to anyone with low PO4 in the system is to go slow and be very careful/conservative with carbon dosing (vinegar, vodka, NOPOX, etc.). While carbon dosing is mainly used to reduce nitrate, it also reduces phosphate (but at a slower rate). If a system is already reading '0' PO4, then the additional phosphate reduction has the very real potential to cause issues.

It would perhaps be safer to first raise PO4 (especially newer systems) to at least detectable levels before starting any form of carbon dosing, IMO.
I wiah I would have or just never dosed it at all. I only did it for a few weeks too! I may have some other type of bloom going on. I was just assuming it was dinos since I hear it comes on when phospates are 0 and gets much worse after a water change so I certainly fit the bill for it. I was feeding corals nightly trying to raise nutrients as well. I wish I knew a way to identify for sure, so I could agressively try to get rid of it so I can go back to waterchanges. I feel like my alk may level out soon as well. It is getting bette r with dropping, I guess because my system is getting used to them. If I wait more than 2 weeks without a waterchange it may get to7.1 or maybe 6 something. I have always been fine with waterchanges alone b4 this bloom, it always kept my alk steady and around 8.5 and nitates 5 after the change then after feeding corals a couple times nitrates would rise to about 10 before I did a waterchange. I am wondering if I can dose alk here and there and not daily dose since its so irratic now because i have a young system and with 30 frags and most very small and only a few sps I shouldnt have to dose alk yet from what my LFS says
 
I get pest algae’s and Cyano when my nitrate to phosphate ratio is not balanced.
When I correct the imbalance they just go away on their own. About 2-3 weeks after correction.
I run phosphates at 1/10th nitrates. Not exact, but close and stable.
My nitrates run 5ppm and phosphates 0.05ppm.

Last time I got pest algae and Cyano, nitrates were 25ppm and phosphate 0.01ppm.

I dose carbon not to lower nitrates but to increase the good algae populations which in turn eat the phosphates which in turn are consumed by corals. Corals can take in nitrates easily, but phosphate, not so much, but they can take in the bacteria which contains the phosphate.

9AD1B055-E378-44FE-8694-EE71FB07AF5F.jpeg
 
Did it every measure soon after you added it? I checked today a few hours later and it detected phos but by the nextday when I usually check it is when its undectable. I dint realize that dinos spripped po4. Pretty sure that what I am dealing with. But my phos was 0 before dinos from carbon dosing and b4 that I used GFO, so it was already low perhaps zero even. I cant remember and cant find my logs.

Yes, it can take some hours before the aragonite rock/sand binds the added PO4. The pace of absorption probably depends on how PO4 depleted the aragonite is. You raise the dose level a bit and keep testing each 24 hours.

The sure way to test is with a cheap student microscope at 400X. Use your phone (zoom in) to take a video. Post that video in the "Dinoflagellates are you tired" thread. Several of us watch that thread and we can ID WHICH dino you have. Treatment protocol can differ according to species.

If you just want to rule in/out dinos at all, you can try the coffee filter test:
Get a sample of the gunk and some tank water in a jar. Shake it up very hard so the gunk kinda dissolves
Pour that through a coffee filter into another clear glass or jar. It should be fairly clear water now.
Place the jar under a good light source for a couple hours then check. If the gunk coagulates it is dinos.
If dinos, then borrow/buy a microscope.
 
Yes, it can take some hours before the aragonite rock/sand binds the added PO4. The pace of absorption probably depends on how PO4 depleted the aragonite is. You raise the dose level a bit and keep testing each 24 hours.

The sure way to test is with a cheap student microscope at 400X. Use your phone (zoom in) to take a video. Post that video in the "Dinoflagellates are you tired" thread. Several of us watch that thread and we can ID WHICH dino you have. Treatment protocol can differ according to species.

If you just want to rule in/out dinos at all, you can try the coffee filter test:
Get a sample of the gunk and some tank water in a jar. Shake it up very hard so the gunk kinda dissolves
Pour that through a coffee filter into another clear glass or jar. It should be fairly clear water now.
Place the jar under a good light source for a couple hours then check. If the gunk coagulates it is dinos.
If dinos, then borrow/buy a microscope.
I get pest algae’s and Cyano when my nitrate to phosphate ratio is not balanced.
When I correct the imbalance they just go away on their own. About 2-3 weeks after correction.
I run phosphates at 1/10th nitrates. Not exact, but close and stable.
My nitrates run 5ppm and phosphates 0.05ppm.

Last time I got pest algae and Cyano, nitrates were 25ppm and phosphate 0.01ppm.

I dose carbon not to lower nitrates but to increase the good algae populations which in turn eat the phosphates which in turn are consumed by corals. Corals can take in nitrates easily, but phosphate, not so much, but they can take in the bacteria which contains the phosphate.

9AD1B055-E378-44FE-8694-EE71FB07AF5F.jpeg
Maybe thats what I have is GHA and cyano or diatoms even. Thats what I thought it was at first because it looks like diatoms and my tank is fairly young, about 7 months old and only had corals for a few months and the xtra lightening because I wasnt running light for months at all then barely before I added corals. Its not snotty nor stringy like dino's or cyano and dosnt have bubbles attached to it. I let it grow on sandbed undisturbed for about 6 days now to see if it would grow longer and bubbles attach but some pieces got longer but no bubbles but on certain areas of glass that has the bloom has bubbles. It came on first after carbon dosing and first water change then I cleaned it up good and it stayed away pretty good until I did another WC and came on even harder so cleaned it up and vacuumed sand through sock and it was back again this time must faster so now I know I cant do waterchanges until I figure this out

Is there any other type of algae that gets bad after a water change? I got a reading of phophates finally about 0.01 so maybe this will go away on its own. I have been dosing vibrant once a week and MB7 2 x a week. My nitrates are 3 ppm so scared to dose carbon again. If It is dinos reef dudes has this youtube with a guest speker and a protocol with carbon, and bacteria's and bubble scrubbing and peroxide I think I will try but does scare me to use the carbon dosing part.
 
Yes, it can take some hours before the aragonite rock/sand binds the added PO4. The pace of absorption probably depends on how PO4 depleted the aragonite is. You raise the dose level a bit and keep testing each 24 hours.

The sure way to test is with a cheap student microscope at 400X. Use your phone (zoom in) to take a video. Post that video in the "Dinoflagellates are you tired" thread. Several of us watch that thread and we can ID WHICH dino you have. Treatment protocol can differ according to species.

If you just want to rule in/out dinos at all, you can try the coffee filter test:
Get a sample of the gunk and some tank water in a jar. Shake it up very hard so the gunk kinda dissolves
Pour that through a coffee filter into another clear glass or jar. It should be fairly clear water now.
Place the jar under a good light source for a couple hours then check. If the gunk coagulates it is dinos.
If dinos, then borrow/buy a microscope.
I finally got a reading of about 0.1 phos. and defiently going to try the coffee filter test tomorrow. I have been racking my brains trying to figure it out and have also let it grow on the sand bed to see if it would get stringy and bubbles attach but a few strings came up but no bubble. Lots of bubbles on areas of glass though. Really looks like diatoms but I dont think diatoms gte bad after a waterchange. Do you know of any algae or bacteria that gets worse after a waterchange besides dinos?

Have you heard of the method that reefdudes has a youtube of? I think its suppose to work on all dinos and should work within 7 days. It includes bacteria's. He espially likes dr tims waste away and one and only. I am using vibrant and MB7. He says one can be substituted but I think its waste away that shouldnt be and that sucks because the vibrant was 40 bucks! LOL. But one should be sludge busting bacteria or big mouth I believe he called it and the other a denitrifying. It also includes bubble scrubbing and and recommends toms aqua lifter and dosing peroxide I think 1 ml per gallon and carbon dosing. I thought I may try that. The carbon dosing scares me since nitrates are 3 and such low phosphates and thats what started this all I believe was nopox.

I was upping coral feeding every night trying to bring up nitrates a little but now I have gone back to 2 x's a week. Do you think I should try to up nitrates more incase I use that protocol or one of the other ones that may require carbon dosing and I know these bacteria's lower nitrates.

I want to thank you for all your replys and helping out a newbie! I tell ya, this is complicated stuff..lol. Hopefully one day it will be smooth sailing! So many other things in my life are being neglected because of the tanks and all of the research!
 
And yes, you should consider dosing two part or kalkwasser to keep your ALK and calcium levels at 7-8. I like ESV 2 part.
I already have BRS 2 part. I like that it came in a set with jugs and the jugs have hand dosing pumps. I a m going to be hand dosing.
Can I just add the alk now and then since it will not regulate the amount the corals want to consume? I have been checking for almost 3 weeks everynight and its always a different amount! and it seems to use less alk the longer the corals have been in system.
 
I finally got a reading of about 0.1 phos. and defiently going to try the coffee filter test tomorrow. I have been racking my brains trying to figure it out and have also let it grow on the sand bed to see if it would get stringy and bubbles attach but a few strings came up but no bubble. Lots of bubbles on areas of glass though. Really looks like diatoms but I dont think diatoms gte bad after a waterchange. Do you know of any algae or bacteria that gets worse after a waterchange besides dinos?

Have you heard of the method that reefdudes has a youtube of? I think its suppose to work on all dinos and should work within 7 days. It includes bacteria's. He espially likes dr tims waste away and one and only. I am using vibrant and MB7. He says one can be substituted but I think its waste away that shouldnt be and that sucks because the vibrant was 40 bucks! LOL. But one should be sludge busting bacteria or big mouth I believe he called it and the other a denitrifying. It also includes bubble scrubbing and and recommends toms aqua lifter and dosing peroxide I think 1 ml per gallon and carbon dosing. I thought I may try that. The carbon dosing scares me since nitrates are 3 and such low phosphates and thats what started this all I believe was nopox.

I was upping coral feeding every night trying to bring up nitrates a little but now I have gone back to 2 x's a week. Do you think I should try to up nitrates more incase I use that protocol or one of the other ones that may require carbon dosing and I know these bacteria's lower nitrates.

I want to thank you for all your replys and helping out a newbie! I tell ya, this is complicated stuff..lol. Hopefully one day it will be smooth sailing! So many other things in my life are being neglected because of the tanks and all of the research!
Bacterias, peroxide, carbon dosing, oh my!

Yes, I am familiar with that bacteria/peroxide method otherwise known as the Elegance Coral method. I would describe the anecdotal outcomes as mixed. I would deploy that only if you had LC amphidinium. Even then...

I'd hold off on all that until you confirm which problem you are trying to solve. Sounding a lot like dinos (WC behavior), but in a newer system it could be some other organism combination. Do the coffee filter thing. If that shows dinos, then you need to buy/borrow a cheap student microscope to ID which dino(s) you have. We have a fairly well established set of protocols for four out of 5 species.

As to dosing 2 Part, unless you have a fair number of stony corals ALK & Ca should not really drop that much.
 
I passed the coffee filter test with no regrouping so I guess its just diatoms. I turned the whites down to only 6 % and seems to be gettinga little better but still there! My problem now is I just discoverd my saltmix is bad and cant do a waterchange for a few days. I guess I will just add some soda ash I have mixed up. Do you know if salt nix is bad if it get moist and you can actually squeeze water out of it? I use reef crystal and used to store in garage(live in Florida) so I decided to bring the new batch in side last time and it still clumped all up and got really moist. I did leave lid off a time or two but will never do that again! LOL

Anyway, I have never checked the water I mix so today I decided to test some left over from what I made last week and it tested 5.9 alk and 6.0 another try! I then decided to mix up a small amount @ 1026 salinty and got same alk. level! I use reefcrystals which is supposed t o have 12 alk I think it is!

Do you think that it could have gone bad? It always does end up getting moist on me though. Is that normal with other brands? This time it got exceptional moist, i could pick up a handful and squeeze water out!.. We had a small flood in our bathroom a few weeks ago and I am constantly getting the floors wet in the den where the tank is and the bathroom is right by the den as well where the flood happened. We got all the water up and put damp rid in the rooms next to bathroom because it seeped into baseboards a little.

One more thing, Being I only had a small amount of water left in bin from last weeks water change the water was very warm to the tune of 88.5 degrees. I use a pump to keep circulation and also pump water into tank and it always heats the water a little bit, maybe to 83 or 84 and then I i wll shut it off and remove lid and it cools back. Is that bad for the water and salt mix? I do have a smaller pump I can use, that dosnt heat up.

My alk is now at 6.5 so since I dont have enough water and cant use this mix I wont be able to do a water change for a few days. I guess its okay to up the alk with soda ash, just maybe to 7.5 for now. I used to be able to keep up alk with weekly to every 10 day water changes but lately barely ups it at all. I may just need a good batch. Thinking of switching to fritz. The reef crystal I have been getting off amazon is half the price of everyone else, like 30 bucks for 160 gallons of mix! Makes me wonder now that I got those readings.. I did add 30 frags after the tank was about 5 months old in a 3 week span and only 36 gallons. About 8 sps. the rest lps and softies. Only 2 good size corals. A big bubble and a big lobo, the rest are small to medium frags. Do you think I should have to dose so soon in a 7 to 8 months old 36 gallon bowfront based on my frags?

Seems like lately If it isn't one thing its another! LOL
Appreciate any advice!
 
I doubt this is the case. In my tank I'm dosing .5ML of a phosphate I make and it raises it daily to .03 then drops to zero the next day. But I know it's not the rocks consuming po4. It's the corals and the cheato. P04 is food for the corals not for the rocks. I dose. Nitrate because it does drop also down to 2.5 which to me is rather low. So I dose about 10ml each ml raises it .1. But like I said I make my own concentrations. If your interested in a cheaper way to dose then buying offshelf stuff let me know.
I’m interested
 

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