Nitrate levels and Acro browning.

[Ryno]

Hello. I wondered if anyone knew what levels of nitrates would cause browning of acro's. Mine have gone from 2-10 in a few weeks (still working on why) and I haven't noticed any corals losing/changing color. My other water parameters are OK but need work. I just ordered a Mg test kit and a PO4 test kit which I'll be checking this week. Last check of parameters were: Ammonia 0
Nitrite 0
Nitrate 10
PO4 0
Calcium 370...........I'm working on this
Dkh 8........dropped because of adding calcium
SG 1.026
I'll have more numbers later but was curious about experiences with nitrate and browning acro's. Thanks.

 

[twilliard]

Kevin can sure answer this for you.

But I think browning is due to high nutrients

 

[twilliard]

Oh


crank up that skimmer!

 

[Ryno]

Skimmer is cranked, thanks. I'm also adding some additional flow to help get rid of dead spots.

 

[tike]

Two things that had caused browning in my corals were high nutrients and low flow. On a 65 gallon i run a etss-500 skimmer and have about 3900gph flow.

 

[Ryno]

Thanks for the response.

 

[kevinpo]

Hello and welcome to Reef Frontiers.
Excellent question! Nitrates in themselves will not cause color change in SPS but are an indicator that other things may be going on. The buildup of tannins which will cause yellowing of the water can reduce the light intensity enough to cause corals to increase their zooxanthellae to the point they begin to look brown. Carbon will clear the water in 2-3 days. Regardless of the amount of skimming over time the water will yellow unless you do one or more of the below:

1. Run carbon.
2. Run ozone.
3. Perform water changes.

Even with no fish, just corals the water yellows. It just takes longer.

HTH,
Kevin

 

[Ryno]

That makes perfect sense, thanks. I do run carbon on occasion and I also "check" my water visually compared to newly mixed SW in a glass.....both look identical. Thanks again.

 

[theJ]

Kevin did an experiment with me one time, where he pulled some water from a fresh batch of mixed water in a white bucket, and compared it to a bucket of old water from one of his curing tanks. needless to say I started running carbon when I got home that evening