The battle of Elevated P04

[Mk2xflow]

Alright first let me start off by saying I have visited numerous multi-paged thread containing various information regarding my issue/question. I am posting this thread in order to get some updated information and hopefully suggestions for problem.

Tank Specs as of today:
90g w/ 30g sump...reef oct skimmer, filter socks(changed 2 per week)
15g water changes done every two weeks, sump vacuumed of detritus
Dosing pump keep alk and calc in check and remains stable at these levels
R/o membrane and filters were replaced a month ago and tds reads 0
I have a two little fishies reactor with 1/2 cup carbon compressed and 60grams of GFO running very slow.
I have been dosing NOPOX to help kep N03 and P04 in check but it only seems to reduce Nitrate.
Feeding is sparce in my opinion, few pellets every day and frozen mysis once every other day that is thawed and drained before going into for feeding (food doesn't get 6 inches down before consumed.
Livestock is barred rabbitfish, two ocellaris clowns, spotted hawkfish, bengai cardinal, small sixline wrasse, cherub pigmy angel, domino damsel, cleaner shrimp

Alk: 9.0dkh
Calc: 422ppm
N03: .25ppm
P04: reads 0 on Hanna sometimes and other times .1-.5
Salinity: 1.025

My problem:

I have been battling Grren hair algae for months with no hope in sight. Now just recently Im seeing cyano on some things, grren hair, other filamentous algae and its driving me nuts. Not to mention I can see very slow growth out of most my sps and lps corals. Zoas seem to do ok in reproducing but even they show signs of poor water quality. So what have I been doing to help? I have been running GFO like stated for a few months to help but it doesn't seem to make a dent, manual removal only does. I tried algaefix for awhile ( 9 doses at least) and saw maybe the tips of hair algae turning white but days later seemed to be growing still. Plus i dont want to have to does Algaefix constantly to keep a algae free tank...i feel i should be able to do it biologically. I turned to carbon dosing (Nopox) to help remove what the GHA what using and in addition run GFO and manual remove what I could but still I have my issue.

I have been told to feed more to help ORP or to bring levels in check but feeding reef roids and mysis and oyster feast or whatever would seem to me like I would just exacerbate the problem. I have been told to run GFO which I have but clearly that hasn't been effective. It would appear to me that my "redfield" ratio has always been out of whack and no matter what i do it stays that way and the coral growth (or lack there of) show me that.

I know i probably missed something but Im at my wits end. My husbandry is way to good and meticulous for me to be having such an ongoing issue with no end in sight. I had a 40g when i first started the hobby that had great success and I had a canister filter that I hardly ever did maintenance on and hardly ever did changes and I never had these algae issues. If my rock is indeed leaching these phosphates, what in gods name can I do to bring everything back to equilibrium. Ready go. and thanks ahead of time for taking the time to help.

 

[mattberrytr]

Fight fire with fire. You should buy or build a waterfall algae scrubber.

 

[Mk2xflow]

Fight fire with fire. You should buy or build a waterfall algae scrubber.

I was considering it but with limited room under the tank in the cabinet I was hoping to not have to incorporate yet another method of nutrient removal.

 

[reefgeezer]

The Redfield Ratio isn't out of whack & it has nothing to do with ORP. It's just that more nitrate is bound in organic compounds created by adding your NoPox than phosphate so phosphate is removed less efficiently. That's the reason for the GFO use when carbon dosing.

Detectable phosphates in a system where algae is already present indicates there is a large amount of phosphate being created/released somehow. Otherwise you would likely see 0 all the time. This could rapidly deplete your GFO.

Test the water coming out of the GFO reactor every day until you figure out how long it takes to deplete the GFO. If it isn't 0 the GFO needs to be replaced.

You might also think about employing Lanthium Chloride to precipitate the free phosphate. This takes some doing so study up first.

Another option is to dose a nitrate compound like potassium nitrate to provide more nitrate to allow more phosphate reduction. Simple feeding doesn't do this effectively because it also adds more phosphate. Ya kinda need to study up on this process also.

 

[mattberrytr]

In that case, I'd add a lot more GFO to your reactor, test phosphate regularly, and replace the GFO regularly. You also want good flow through the reactor. At least 2x the total water volume flowing through it every hour.

 

[Mk2xflow]

The Redfield Ratio isn't out of whack & it has nothing to do with ORP. It's just that more nitrate is bound in organic compounds created by adding your NoPox than phosphate so phosphate is removed less efficiently. That's the reason for the GFO use when carbon dosing.

Detectable phosphates in a system where algae is already present indicates there is a large amount of phosphate being created/released somehow. Otherwise you would likely see 0 all the time. This could rapidly deplete your GFO.

Test the water coming out of the GFO reactor every day until you figure out how long it takes to deplete the GFO. If it isn't 0 the GFO needs to be replaced.

You might also think about employing Lanthium Chloride to precipitate the free phosphate. This takes some doing so study up first.

Another option is to dose a nitrate compound like potassium nitrate to provide more nitrate to allow more phosphate reduction. Simple feeding doesn't do this effectively because it also adds more phosphate. Ya kinda need to study up on this process also.

Is there any other way of balancing nitrate with phosphate instead of dosing nitrate? I can test the gfo but I have been replacing it weekly.

 

[reefgeezer]

Is there any other way of balancing nitrate with phosphate instead of dosing nitrate? I can test the gfo but I have been replacing it weekly.

There really isn't. There's no way around it. More nitrate is removed than phosphate when organic compounds are produced. You either have to raise the nitrate level so more organic compounds will be created thus using more phosphate or simply reduce the free phosphate.

Dripping Lanthium Chloride (LC) into a filter sock is a great way to remove large amounts of phosphate. LC is cheap and available at the pool store. There are lots of threads here @ RC about it and many who can better answer specific questions about it than me. I'd consider using it.

An ATS might be a long term answer. I tried it without much success, but I'm not patient. I prefer GFO or LC. FWIW, manual removal of the algae in the DT also exports phosphate.

Multiple 50% water changes are a good way to drop phosphate levels rapidly. Obviously the levels will rise, but it gives the GFO a head start.

 

[garwood]

how old is tank. what kind of rock.

 

[reefgeezer]

As you said in your OP, it could be the rocks leaching phosphate. That's an easier fix than you might think. Search on "Acid Bath".

 

[slay]

I start with 1 gram of GFO per gallon for my tanks and work my way up from there if I still have NO4 problems. I currently run a little more than 3/4 of a cup (I think 175 grams) on my 75 gallon. You certainly can use too much tho, and you should increase the amount slowly, but 60 grams for a 90 gallon tank is quite low in my opinion.

 

[Ucantwin]

In that case, I'd add a lot more GFO to your reactor, test phosphate regularly, and replace the GFO regularly. You also want good flow through the reactor. At least 2x the total water volume flowing through it every hour.

I just started using GFO on my 75 gl and it seems my water barely flows through the reactor, maybe 30 gph. Anymore than that and it seems the GFO does not tumble on the surface but sprays all over in the reactor. Am I doing something wrong?

 

[MrCaveman]

My rocks were leaching phosphate for about 6 months. I continued replacing Rowaphos during that time until most of the phosphate bound up in the rocks had eventually dissipated. I fed very sparingly, 0tds, N03 was was always below 1ppm but always had PO4 measuring from .07-.12 for months. The rocks strive to reach a PO4 equilibrium with the water column until it runs out. I bought the LC and 10 micron socks but I got too nervous to actually carry on with the procedure fearing my acros and tangs would be negatively affected if doing it in tank. I was going to put the rocks in a tub and then do the LC but then the PO4 began dropping to 0 from the Rowa a few weeks later.

 

[MrCaveman]

I just started using GFO on my 75 gl and it seems my water barely flows through the reactor, maybe 30 gph. Anymore than that and it seems the GFO does not tumble on the surface but sprays all over in the reactor. Am I doing something wrong?

30gph is fine if its tumbling properly. Itll only take about 2-3 hrs to react with your tank volume

 

[wildman926]

I was considering it but with limited room under the tank in the cabinet I was hoping to not have to incorporate yet another method of nutrient removal.

If you have a standard 90g, you have plenty of room under there. I run a 30g sump, protein skimmer with waste collector, chaeto reactor, and an ATS. ATS sits on top of converted 30g wet/dry sump. Here is an old pic, but it does not show chaeto reactor, which actually sits on the other side of the waste collector -

 

[Kt8]

Brightwell phosphate E worked good for me. I had the same problem, and it got too costly to keep changing gfo every couple of days. A little goes a long way. I dripped it in front of my skimmer as directed and had no problems and lowered my phosphates.