Reason why phosphate remover cause RTN

[icliao]

I heard some interesting theory on why phosphate remover cause SPS RTN.

Some one claims that Phosphate is an element that utilized by DeNitrification bateria extensively.
In an environment that is high on Nitrate, the DeNitrification process is especially active and if Phosphate was removed quickly without dealing with the input of Nitrogen source, there will be a sudden increase in NH3 and NO2 which causes RTN.

Is that true?

[dragonladylea]

tagging along for this one.

[gemxsps]

Well.. I don't trust phosphate remover that much..
You think phosphate remover completly remove phosphate ?
No.. Any plant can not survive without phosphate but some bubble algae can survive under a lot of phosphate remover. I think it removes a lot of phosphate but not all. So I don't think it makes RTN.

[icliao]

While it might be true that PO4 remover doesn't remove all phosphate, my question is could PO4 remover cause the increase of NH3/NO2 at least temporally which link to SPS's RTN.

[Serioussnaps]

phosphate removers can swing ALK levels if used in higher dosages

also you are on to something with the nutrient theory...but in most cases i would think it would be to change in ALK...

you may be way ahead of my thinking on this one but i dont think that the removal of P04 will cause such a fluctuation in Nitrate.....

i think you should swing this one over to Randy in the chemistry forumn and see what he thinks for sure...

very interesting

[lduncan]

It's nothing to do with removing anything too quickly. You're adding something.

In this case you're adding iron. Corals have a variety of responses to this, depending on the amount added, previous exposure etc.

[TwistedTiger]

Originally posted by Serioussnaps
phosphate removers can swing ALK levels if used in higher dosages

Although I had no problems with my SPS phosban did lower my Alk greatly in a short period of time. If you're using large amounts I'd test Alk often and add buffer as needed.

[REEF-DADDY]

Originally posted by TwistedTiger
Although I had no problems with my SPS phosban did lower my Alk greatly in a short period of time. If you're using large amounts I'd test Alk often and add buffer as needed.

Agreed, its the ALK. I got sloppy with my waterchanges and did not test and adjust alk on a new bucket on salt mix. Changed 80 gallons on a 400 gallon system. Dropped alk about 1 dkh and BAM! got some rtn.

I've never bought the nutrient theory. We take these corals from the sea and ship them all over the world, cut them, dip them, I don't even acclimate my sps. No issues at all. As long at the alk is right.

If you have measureable po4 and drop in GFO you will see a significant drop in alk.

[Dr. JMadscientist]

Also keep in mind that SPS contain zooanthelle which is algae. In high phosphate tanks, they become dependent on the phosphate to feed their zooanthelle and utilize less light. These corals are usually brown. When you strip the phophate out, it takes out their primary food source for the zooanthelle and they then rtn because they can not adapt to using the light overnight.

IMHO, if you remove the phosphates slowly over the course of 3 weeks to a month, the corals have ample time to adjust to the change.

[Fliger]

I believe its a combination of an alk swing, and the addition of iron - when carelessly used. If you don't watch your alk, or use too much GFO for the size of your tank, it will drop your DKH like a rock. And if you use in a fluidized bed and don't rinse it well, GFO dust will coat your tank. Just MVHO.

I've been using GFO's for probably a couple years in a fluidized reactor and have never had an issue with it.

[Fliger]

Regarding po4 drops being the cause - no way IMO. I've seen SPS go from one tank to another with a huge variance in po4 with no ill affects. Just the opposite, if you take an ailing SPS from a bad tank to a steady healthy tank, it will recover extremely fast.

[Serioussnaps]

phosphate drops can IMO cause some problems....just not due to a rise in nitrate because of a lowering of phosphate...first i am not even sure(and i dont believe it will) that if phosphates are lowered through a GFO that there is some mechanism missing to convert nitrate...there wont be a nitrate rise and the lowering of phosphate wont even be the cause

only problem with lowering phosphate to fast and this is a fact....it can cause accelerated growth in stony corals...thus cause a precipitation of calcium carbonate and thus a lowering of the alk.....this lowering of ALK is what causes the RTN...in some cases it can be severe lowering....

i just started using my TLF phosban reactor with 150g's of phosban media 1 week ago and the ALK dropped from 9.15 to 8/8.15...a full DKH!! and that is without any corals in the tank!!!! so you must be careful...i bet if my tank was full of ACROS s we would have been seeing come RTN or STN this week...but luckily im not the dummy making big changes after i get corals but do it before

by the way my ALK stayed constant by dripping kalk and nothing was changed but the GFO added to tank....i can safely and 100%positiviely say that the phosban use in the reactor caused this ALK swing...i dont know if 1 dkh is that bad considering it took it 6.5 days to do so...but anyhow it illustrates the dangers of GFO's particularly for someone who already has their tank stocked

i think the theory brought up in the original post is false...i am gonna ask Randy even though i know he is going to agree with me

[robitreef]

Just a suggestion, but this thread may get some answers if it was moved over to the reef chemistry forum, so that Randy can put his two cents in.

[Serioussnaps]

thats what i said....im basically saying what Randy is going to say anyways

[Mike O'Brien]

IMO it's the sudden change in phosphate level's associated with using too much too soon, and sometimes the addition of iron.

[Horace]

Im not entirely sure why this occurs but it is not exclusive to GFO. This will also happen with Zeovit if your flow through the zeoliths is too agressive. I have heard about RTN occuring when you run carbon too agressively as well if your tank isnt used to it. I think it is more than just a matter of an alk swing...I think these products simply cause massive change in water quality in a short period of time and this can shock corals and cause RTN. Thats my theory but I am no scientist and sertainly have not done any research...