Eating my coral?
 

Gone for 5 days, and I find a large portion of my corals have turned almost to skeletons. I've been battling high nitrates and using nopox, I've done days worth of large water changes and the nitrates drop for the day and then back over 100 the next day. Bare bottom tank, lots of live rock...

What's happening
Ca 400
Alk 7
Mg 1140
Nitrates 100ish... no missing livestock.

Can’t tell from the pic but usually asterina unless the red center target Coral, when Coral dies the skeleton can grow a light film of algae which is possible that’s what the amasterina wasn’t feeding on?

Tang Daddy, there is no algae growing on the skeleton, I'm just lost as to what's happening in this tank.

at nitrates over 100 little no no coral will be able to survive for any length of time, I'm surprised your fish are alive

You need to do a few big % wc and figure out where that nitrate is coming from ? pellets spilled ? something dead?

whats you phosphate level? if nopox is stripping phosphate to 0 ppm your corals will be hurting.

Nopox is for NO3 more so than PO4, your thinking about GFO.

Nopox is usually used for no3, but it does reduce po4 as well. It is possible to strip too much if used in conjunction with GFO, macros, etc.

What is the age of the tank? Pictures? What type of corals? Lights?

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And how much nopox are you dosing?

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Dosing Nopox at the recommended dose 4mls per day. There is no dead livestock, not running gfo, I've done a bunch of 75% water changes and again the Nitrates drop for the day and then are back at 100 the next day or two. Bare bottom tank, decent coraline algae growth, 4 clown fish and some snails.

In a desperate attempt to fix things I cleaned all the live rock and moved everything into a 75 gallon tank with new water. I did transfer about 20 gallons of the old water to the new tank. I'll check the levels tomorrow.

Shouldn't be anything the asterina is doing. They'll just be slurping the dead/decaying coral tissue probably.

My nopox bottle says highest dose is 3 ml per 25g per day above 10. Is it recommended to use 4 ml when they are so high?

You mentioned you were gone for 5 days. Do you have a dosing pump or did someone do it manually for you?

Have you tested for nitrites, ammonia?

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