TOC and coloration

[A.G]

Hello,

I came from the same notion where every one thinks that Po4 and No3 alone ( i know light etc but am referring to water here) affects colors. Well I i guess thats not all ...

Recently I have been strugging as many of you have with pale , very light colored sticks and I do not use GFO .

Only a skimmer and Bituminios GAC from BRS ( in a reactor) . I use one table spoon for my 34g tank changed weekly. Thats less than thier recommandation.

Now I thought that GAC has nothing to do with N and P which are undetectable using Salifert.

I decided to removd GAC and withen a week i noticed my corals coloring up. I had a purple death paly that never showed that purple color untill that GAC is removed. Some may say that its due to reduced water clearity but I dont think so.

That purple paly were pretty shaded from the begining. I thought why not try to fire the Reactor again, i lost that colors on my sps and purple death became less and less purple.

So I think its not only P and N but also organics ?

Please share your thoughts on this

 

[A.G]

This actually brings something else to my mind. Food is organic so could it be that some ppl are having zero no3 due refugium etc and are feeding thier thank pretty heavily ( raising the organics) which "may" explain why some get good colors by simply feed more? While still have thier NO3 at zero...

 

[markalot]

When I think about GAC I think about crystal clear water ... a desert for SPS corals. Removing GAC usually makes the water less clear, maybe more particulates in the water the corals can feed on?

 

[kevin_e]

Carbon usually removes discoloration by removing impurities, GFO will remove nutrients. I don't run either anymore after having pale corals. I just run a skimmer and chaeto. I feed heavily.