GFO and controlling phosphates

[Gtinnel]

For the last year or so my phosphates have been pretty consistent around .05, until I checked them late last week, where they had gone up to .20. Another user recommended that I use GFO, which I had on hand so I put 6TBS (well below the suggested amount) in a media bag and put it in my sump. I checked 2 days later and my phosphates were down to .07. Then today I checked them (so another 2 days later) and they're back up to .15.

My tank is a 125g and I used a small amount of gfo, so has it already gone back up because I depleted that gfo in 4 days? Should I replace the gfo and if so should I add more this time? Is the constant small swings harder on the corals than just leaving it at the slightly elevated levels? I've used gfo in the past and over did it leading to dinos so I'm afraid to use too much.

I plan on trying to maintain it long term with a refugium and chaeto, but I'm just trying to get them down with the gfo while I'm waiting on getting my refugium setup.

 

[sunken3]

i use phosphat-e to reduce my po4 and gfo to maintain them. I kind of see gfo as a sponge.. it absorbs and then it is done.. so you need to add enough to deplete and maintain, or switch it out when depleted.

 

[outhouse]

I've used gfo in the past and over did it leading to dinos

It may have been coincidental, never once had dinos in 30 years and keep my water at time undetectable for nitrates and phosphates. Generally Dinos are a product of new tanks.

in a media bag and put it in my sump.

usually not the way to use GFO, so I doubt it absorbed to capacity. Im guessing based on your testing such a small amount in a bag is not absorbing as fast as your tank is being fed. I used inline media containers exactly like my DI containers and you should be using half a cup at minimum.

 

[outhouse]

Is the constant small swings harder on the corals than just leaving it at the slightly elevated levels?

The swings are not noticed, Higher levels are, but only critical if left that way for longer periods with rising levels. At higher levels with high nitrates will usually bring on GHA or other pest algae long before your corals are stressed.

 

[BrianReefer]

Did you confirm that phosphate level with an ICP test and/or a few manual tests? I’d do that before actioning. My Hanna ULR reads consistently higher than what ICP (or other test kits) report so I’d be cautious of starting a remediation plan without being certain there’s an issue first. Though I do get the uptick vs prior testing, but I’d still validate first before starting GFO in case those numbers are elevated

 

[Gtinnel]

i use phosphat-e to reduce my po4 and gfo to maintain them. I kind of see gfo as a sponge.. it absorbs and then it is done.. so you need to add enough to deplete and maintain, or switch it out when depleted.

If I add more gfo than last time does it cause the phosphate to drop lower, or does it just cause it to last longer? If you use the sponge analogy then I would think that adding more would just drop the phosphates lower until they reach 0, which I definitly want to avoid.

I've don't know anything about phosphat-e, but ultimately I plan on having the refugium setup next week if all goes as planned. So buying and waiting on shipping of another product isnt worth it for me.

 

[Gtinnel]

usually not the way to use GFO

I'm aware in a reactor is the preferred usage, but was just trying to get a cheap and easy, temporary solution to drop my phosphates

My nitrates have tested just a little over 5 the entire time. Everytime I've tested phosphate I've tested for nitrate as well.

 

[Gtinnel]

Did you confirm that phosphate level with an ICP test and/or a few manual tests? I’d do that before actioning. My Hanna ULR reads consistently higher than what ICP (or other test kits) report so I’d be cautious of starting a remediation plan without being certain there’s an issue first. Though I do get the uptick vs prior testing, but I’d still validate first before starting GFO in case those numbers are elevated

No I did not perform multiple tests. The only phosphate test kit that I have is the Hanna ULR, so I can't use another brand to verify its results with, but I see your point. Next test tomorrow I will go ahead and perform it twice. Although I've never had any reason not to trust the Hanna in the past.

 

[Schraufabagel]

I’m assuming you have a tank with a sump given that it’s 125 gallons. Your GFO would be far more effective and consistent in a reactor. I keep mine in a bag in my AIO due to space restrictions (and lack of quality in stock hang on reactors), and I start to see spikes after the GFO has started to turn into a brick. Mainly because there’s nothing to keep it separated in a media bag

 

[Gtinnel]

I’m assuming you have a tank with a sump given that it’s 125 gallons. Your GFO would be far more effective and consistent in a reactor. I keep mine in a bag in my AIO due to space restrictions (and lack of quality in stock hang on reactors), and I start to see spikes after the GFO has started to turn into a brick. Mainly because there’s nothing to keep it separated in a media bag

I do have a sump but space is an issue, plus I'm not wanting to setup a reactor, because I'm hoping to not keep using gfo regularly.

 

[Captain Hook]

Ever get your po4 under control @Gtinnel ?

 

[Gtinnel]

Ever get your po4 under control @Gtinnel ?

Not as well as I'd like. I'm still going through the constant cycle of periodically adding small amounts of gfo. I have started using reefroids more frequently and I'm wondering if that is contributing to the varying levels I'm seeing.

 

[Captain Hook]

Not as well as I'd like. I'm still going through the constant cycle of periodically adding small amounts of gfo. I have started using reefroids more frequently and I'm wondering if that is contributing to the varying levels I'm seeing.

Ah okay, how bout your fuge? You get that up n going? If it makes you feel any better I just tested my phosphates for the very first time and it’s .32 and my nitrates are 20ppm I’m only running a canister filter though, and feed heavy. Gotta get myself a sump built with a filter roller, skimmer, and fuge just limited on funds atm.

 

[Gtinnel]

Ah okay, how bout your fuge? You get that up n going? If it makes you feel any better I just tested my phosphates for the very first time and it’s .32 and my nitrates are 20ppm I’m only running a canister filter though, and feed heavy. Gotta get myself a sump built with a filter roller, skimmer, and fuge just limited on funds atm.

Yes the fuge is up and running and since adding the chaeto it has probably quadrupled or more in size. It can still probably about double its current size before it fills up my 12 or so gallons of fuge space.
I'm still fluctuating phosphate between about .08 and .16, which honestly isn't to bad, but it bugs me because it used to be stable right around .05. My nitrates have been stable at 5-7 everytime I test (which for both nitrate and phosphate has been nearly daily for the last month). I'm not sure what changed to make my phosphate fluctuate like it is. I have been reading that apparently reef roids can greatly raise it. So now I'm going to track when I add reef roids and see if it relates to when my readings are elevated.
The whole time I've never seen any negative effects on my corals so I'm probably worrying about nothing honestly.

 

[Dorsetsteve]

Reef roids is loaded with Phosphate, unless you have some measurable benefit I’d stop using it. Your left hand is fighting your right.

 

[gbroadbridge]

For the last year or so my phosphates have been pretty consistent around .05, until I checked them late last week, where they had gone up to .20. Another user recommended that I use GFO, which I had on hand so I put 6TBS (well below the suggested amount) in a media bag and put it in my sump. I checked 2 days later and my phosphates were down to .07. Then today I checked them (so another 2 days later) and they're back up to .15.

My tank is a 125g and I used a small amount of gfo, so has it already gone back up because I depleted that gfo in 4 days? Should I replace the gfo and if so should I add more this time? Is the constant small swings harder on the corals than just leaving it at the slightly elevated levels? I've used gfo in the past and over did it leading to dinos so I'm afraid to use too much.

I plan on trying to maintain it long term with a refugium and chaeto, but I'm just trying to get them down with the gfo while I'm waiting on getting my refugium setup.

GFO needs to tumble to expose surface area so is best used in a reactor. I'm dumped tablespoons in a filter sock and it stops working pretty fast unless you shake it a few times a day.

Also, Reef Roids are phosphate on steroids, you only need a tiny amount and that tiny amount will create a phosphate spike. I use it maybe once a week, but generally use Reef Energy plus feeding the fish well to keep coral happy.


Regards
Graham.

 

[Gtinnel]

GFO needs to tumble to expose surface area so is best used in a reactor. I'm dumped tablespoons in a filter sock and it stops working pretty fast unless you shake it a few times a day.

Also, Reef Roids are phosphate on steroids, you only need a tiny amount and that tiny amount will create a phosphate spike. I use it maybe once a week, but generally use Reef Energy plus feeding the fish well to keep coral happy.


Regards
Graham.

I knew that a media bag wasn't the ideal setup but I'm really not wanting to use gfo long term, so I didn't want to set up a reactor unless necessary. I never honestly considered the fact that the gfo on the outside of the bag was being depleted and the gfo on the inside wasn't getting enough flow to work. That would make sense, it does turn into a fairly dense ball of gfo once it gets wet.

I had always heard that reef roids were high in phosphates, but it wasn't until recently that I was reading that they're apparently really, really high in phosphates. I don't see any real difference in my SPS adding it, so I'll probably just quit for a while and see what happens with my phosphates.

 

[SPR1968]

For the last year or so my phosphates have been pretty consistent around .05, until I checked them late last week, where they had gone up to .20. Another user recommended that I use GFO, which I had on hand so I put 6TBS (well below the suggested amount) in a media bag and put it in my sump. I checked 2 days later and my phosphates were down to .07. Then today I checked them (so another 2 days later) and they're back up to .15.

My tank is a 125g and I used a small amount of gfo, so has it already gone back up because I depleted that gfo in 4 days? Should I replace the gfo and if so should I add more this time? Is the constant small swings harder on the corals than just leaving it at the slightly elevated levels? I've used gfo in the past and over did it leading to dinos so I'm afraid to use too much.

I plan on trying to maintain it long term with a refugium and chaeto, but I'm just trying to get them down with the gfo while I'm waiting on getting my refugium setup.

I use rowaphos in both my systems 24/7 and heavy and I can’t say I consider that using GFO and keeping low phosphate levels causes dinoflagellates, not in my experience anyway. I’ve used it from day one in my new large system and skipped the ugly stage by doing this.

You really do need to have it in a reactor for it to work properly, and yes I would change it and keep changing it and keep phosphate less than 0.03 and you will avoid many of the problems we constantly read about. If you don’t change it when spent phosphate will rise.

I change rowaphos every 4-8 weeks depending on the amount used and hardly ever need to test phosphate because it’s always very low

Talking about reef roids, you don’t need to add much at all depending on your nutrient levels, I use it and/or reef energy once every few weeks if that, In both my systems, possibly less than once a month.

 

[Gtinnel]

f you don’t change it when spent phosphate will rise.

I am intrigued by this statement. Do you mean that phosphates that were absorbed by the gfo will be released back into the water if the gfo isn't replaced, or at least the old is removed?

As for dinos when I first started my current tank I was stupidly under the impression that 0 nitrates and phosphates were best. My nitrates were always 0 and I started gfo in a reactor to where my phosphates were 0 as well. Not surprisingly, looking back at it, I couldn't keep a coral alive and I ended up with a Dino problem. Once I removed the gfo my phosphates naturally settled around .05 (until recently) and I started dosing nitrates to get them between 2-5.

I don't know if accidentally over using gfo and dropping phosphates to 0 would cause another Dino outbreak, but it's a risk I'd rather avoid. Honestly as I am to some degree chasing numbers on my phosphates my corals are looking better than they ever have. To be fair though I've also had a few equipment changes in my tank including more powerheads and new lights around around same time that I saw elevated numbers.

 

[jrill]

I’m assuming you have a tank with a sump given that it’s 125 gallons. Your GFO would be far more effective and consistent in a reactor. I keep mine in a bag in my AIO due to space restrictions (and lack of quality in stock hang on reactors), and I start to see spikes after the GFO has started to turn into a brick. Mainly because there’s nothing to keep it separated in a media bag

Mix it with carbon