LifeRock absorbed all Phosphates

[nornicle]

Hi all - I have been struggling to keep sps in my tank, bare bottom, ICP is green on all fronts and nitrates around 2.5ppm% however phosphates KEEP bottoming out to the point where I will dose 0.04ppm phosphate (using seachem and then measured using Hanna) and put in a teaspoon of reefroids with no visible algae problem and still measure 0.00 in the Hanna a day or two later.

I turned my fuge lights off as my sps were all bleaching out. I reduced the lights. My sps all went pale and some bleached.

the common point is the tank is 100% caribsea life rock... what to do??

 

[jda]

Unless you have a hannah ultra low that says that you have less than 1 ppb, then you very likely have enough residual phosphate. Keep on feeding your fish a bunch since the ammonia/ammonium (for nitrate) and the many forms of phosphorous/phosphate/organic/inorganic from the fish waste is the prize, not the one kind of P that you are dosing which likely is just getting bound up by the rock.

 

[tehmadreefer]

Well, it is absolutely true and very well established (both in the scientific literature and in hobby testing) that bare calcium carbonate readily absorbs phosphate, and it can be a truly staggering amount.

One pound of Florida aragonite rock was shown to bind 57 ppm of phosphate from 5 gallons of water, leaving only 0.16 ppm in the water.

Phosphate Absorption Rates in Aragonite

The more you add, the more will bind!

www.reef2reef.com

Ok and then what happens to the po4 once in the rock?

 

[nereefpat]

Ok and then what happens to the po4 once in the rock?

It balances with the levels in the water.

If you remove P in the water with GFO or a water change, the P can leach out of the rock into the water. If you add more P to the water, the rock (and sand) can absorb more.

 

[Randy Holmes-Farley]

Ok and then what happens to the po4 once in the rock?

As nereefpat states, it is in constant on/off equilibrium between the rock surface and the bulk water. If you perturb that equilibrium by adding or removing phosphate from the water, it shifts more onto the rock or off of it.

 

[TheDuude]

I started my tank 1 year ago with Marco dry rock and am also struggling to keep phosphate stable. I am currently dosing Po4 to keep them detectable around .04. If I stop the dose I notice my corals start to suffer and soon my po4 bottoms out. This is my first tank starting with 100% dry rock and I have to say I have never experienced so many issues in the first year of a tank as I have with this one. It has been extremely difficult to get No3 and po4 stable.

 

[Timfish]

Don't rule out the roles of biofilms and sponges with the carbon, nitrogen and phosphorus cycles. Also, keep in mind we can only test for dissolved inorganic forms of carbon, nitrogen and phosphorus. We can't test for particulate or dissolved organic forms which may be playing a more important role than the inorgainc forms.

 

[nornicle]

As nereefpat states, it is in constant on/off equilibrium between the rock surface and the bulk water. If you perturb that equilibrium by adding or removing phosphate from the water, it shifts more onto the rock or off of it.

Hi Randy - so for those of us using dry rock and bare bottom, how do you suggest we set up a more stable PO4 reading without going overboard?

So far I have dumped in 1/4 teaspoon reefroids daily, and dosed seachem excel phosphorous when it has hit zero, and also dosed amino acids. I have also increased feedings with frozen food and nori.

 

[Randy Holmes-Farley]

Hi Randy - so for those of us using dry rock and bare bottom, how do you suggest we set up a more stable PO4 reading without going overboard?

So far I have dumped in 1/4 teaspoon reefroids daily, and dosed seachem excel phosphorous when it has hit zero, and also dosed amino acids. I have also increased feedings with frozen food and nori.

Some folks use dry rock that is loaded with excessive phosphate, and they have a bad time trying to get rid of all of it. Lanthanum chloride treatment before adding it to the tank is a good bet.

Some folks use dry rock with no phosphate on it, and they will have to feed heavily (and deal with the nitrate) or dose phosphate to attain a reasonable level in the water.

 

[ELChingonsReef]

So I've found out the hard way that Liferock has completely absorbed all phosphates in my tank causing a STN event to half my SPS and a Diatom bloom on the sanded.

The tank has been setup for about 1 year and I was struggling with keeping phosphates at decent levels for the first 4-5 months.I speculated that the liferock was absorbing it as I've read it a few places (but not a lot of info on it anywhjere) and talking with some SPS pros saying that dry rock would be absorbing it. About the 6th month is when I could tell things were getting good in the tank, levels were getting ideal and all corals have been thriving, great color and growth. So I figured the rock had finally stopped absorbing and completely cured.

Then about 10 days ago I put some spare LifeRock in the back chambers just to add more room for bacteria, pods, critters, etc. and then of course I went on a 5 day trip and came back to things looking off. Polyps on half the SPS not extended and I notice the Coraline algae was fading quickly.I test all nutrients and find Phosphate and NO3 complete at 0. I used two different test kits for both to confirm.

Now I have a small tank (20g) so adding a couple pounds of rock was actually a very significant Phosphate remover. I had no other chemical media running the whole time and skimmer was working fine but its not strong enough to pull nutrients like that. Plus I also have heavy fish load and feed at least 2-3 times a day. So the only change to the tank was the LifeRock.

I have since removed 70% of the new rock I added to the tank and have turned off skimmer and been feeding heavily, using reef roids and dosing a small amount of No3 and Phosphate to help get the rebound going. Things are looking slightly better now on day 2 of fixing the problem.

So just a heads up to people regarding Dry Rock and phosphate removal, curing the rock before hand is a must in my opinion.

I'm having the same problem. I started my tank with dry rock 1.5 years ago. I have a lot of sps corals. I have not experienced stn yet but I dose phosphate daily to keep itbat 0.03. I was even thinking of putting phosphate on a doser. My question is eventually that Sry rock will reach its limit and not be able to bind anymore then what's going to happen? Am I going to get a big phosphate problem.? That's what I'm worried about. I'm already a year and a half into it. It should be happening soon I would think. What do you think?

 

[I never finish anythi]

Interesting topic

 

[mfollen]

Adding to this great thread (thanks all!) with a request so that reefers with mostly caribsea’s liferock know what to do to avoid an excessive binding and eventual release of the inorganic po4 we dose to our systems. This could help prevent potential future issues and to understand how to best handle this binding issue in our system.

My reef is 10 months old now (bare bottom) and I’m still dosing 55 ml of neophos daily on top of feeding the fish with an autofeeder 7 times a day. The Neophos and neonitro dosing along with the feedings is keeping my levels at 0.7 po4 & 10 no3, which is my target levels for my acro and zoanthid dominant species on the system.

So for all the reefers such as myself with these popular rocks who are dosing inorganic nutrients to maintain a target level to keep our corals happy, what should we do?

Continue dosing to keep hitting our target levels, with the understanding that eventually we may need to stop po4 dosing and implement aggressive po4 removal?
Stop (or slowly decline) dosing and let the nutrient levels fall to below target levels, to allow the nutrient balance to maintain the natural levels from feeding alone?

When phosphate and nitrate fall to lower levels I notice my zoas not as puffed and happy and acros more thin and pale. I also notice more microbial imbalance towards some of the nasties (cyano and dino).

Thank you

 

[ELChingonsReef]

Adding to this great thread (thanks all!) with a request so that reefers with mostly caribsea’s liferock know what to do to avoid an excessive binding and eventual release of the inorganic po4 we dose to our systems. This could help prevent potential future issues and to understand how to best handle this binding issue in our system.

My reef is 10 months old now (bare bottom) and I’m still dosing 55 ml of neophos daily on top of feeding the fish with an autofeeder 7 times a day. The Neophos and neonitro dosing along with the feedings is keeping my levels at 0.7 po4 & 10 no3, which is my target levels for my acro and zoanthid dominant species on the system.

So for all the reefers such as myself with these popular rocks who are dosing inorganic nutrients to maintain a target level to keep our corals happy, what should we do?

Continue dosing to keep hitting our target levels, with the understanding that eventually we may need to stop po4 dosing and implement aggressive po4 removal?
Stop (or slowly decline) dosing and let the nutrient levels fall to below target levels, to allow the nutrient balance to maintain the natural levels from feeding alone?

When phosphate and nitrate fall to lower levels I notice my zoas not as puffed and happy and acros more thin and pale. I also notice more microbial imbalance towards some of the nasties (cyano and dino).

Thank you

Yeah I'm not looking forward to the days of GFO in the future. But I was thinking when that day comes I may dump a large peice of dry marco rock in the sump to continue the phosphate deficiency for a while longer. GFO is not something I want to start using unless I absolutely have to. It seems that as acropora frags turn into colonys they are more sensitive to p04 swings. Or any other swing. In my experience sps frags are more forgiving.

 

[Randy Holmes-Farley]

Yeah I'm not looking forward to the days of GFO in the future. But I was thinking when that day comes I may dump a large peice of dry marco rock in the sump to continue the phosphate deficiency for a while longer. GFO is not something I want to start using unless I absolutely have to. It seems that as acropora frags turn into colonys they are more sensitive to p04 swings. Or any other swing. In my experience sps frags are more forgiving.

While adding bare rock to bind phosphate is a seemingly fine plan (if it works), I don't see how it is fundamentally different than GFO. Both bind phosphate to the mineral surface, and the amount of binding depends on how much you add/use.

If you want a small effect in either case, use a small amount.