Cant keep Zoas in my reef tank

[justfbilly]

I have an established reef tank that has been up and running for over 2 years. It is a 75 gal tank with a 30 gal. sump and T5 lights with Metal Halides. My issue is that I cant keep a Zoa alive in this tank? I have tried placing them at every level in the tank, varied water currents and lighting. All of my other corals are doing great and are healthy.

My water parameters are:

Salinity : 1.025
PH: 8.3
Temp : 81
Ammonia: 0
Nitrite: 0
Nitrate: 0
Phosphates: .13
Calcium: 420

I have a 45 gallon fish only tank and I placed some zoas in this tank just to see what they do. Well the Zoas are growing like crazy in the fish only tank? Is the reef tank too clean for Zoas? Does anyone have any ideas or suggestions on what I can try? Or should I just give up on having Zoas in my reef tank?

Thanks

 

[Sawen]

I had the same problem and found my answer about one month ago after losing scores and scores of zoas over a two year period.

I found my answer after pointing a flashlight into my tank in the middle of the night.

Two gorillas crabes eating the heads of my zoas one after the other.

In the morning, most others were irritated and closed. All polyps were eaten after a week or two depending on how many I had bought.

I suspected lighting, flow, copper and all sorts of other things but not this.

 

[Jone]

NO3 should be around 4ppm..dose Potassium Nitrate or Sodium Nitrate til you get 4ppm in your tank and keep it there (do a search of how to dosing nitrates)...run gfo to make your PO4 non detectable,,run a reactor of GAC too..keep Alk 9-10 DKH..Your Calcium looks fine but what is the Magnesium level ?? Lower your temp to 78 degrees ,no big fluctuations..Water change schedule ?? Flow,,zoas like more flow than you think,,Lighting is sometimes another issue,,,I feed rotifers and phytoplankton daily..

 

[SIR PATRICK]

NO3 should be around 4ppm..dose Potassium Nitrate or Sodium Nitrate til you get 4ppm in your tank and keep it there (do a search of how to dosing nitrates)...run gfo to make your PO4 non detectable,,run a reactor of GAC too..keep Alk 9-10 DKH..Your Calcium looks fine but what is the Magnesium level ?? Lower your temp to 78 degrees ,no big fluctuations..Water change schedule ?? Flow,,zoas like more flow than you think,,Lighting is sometimes another issue,,,I feed rotifers and phytoplankton daily..

All great advice, and good questions.