Help - Can you tell what may be wrong?

[jwill275]

My Zoanthids are not doing well, my water parameters are: Amonia, Nitrite, Nitrate - all 0. PH 8.3 - Alk 8 dkh, Calcium 380-400.
Thanks

 

[spiderwoman]

What is your lighting and flow? How close to the lights are they?

 

[spiderwoman]

Also you may want to do a FW dip on them to be sure there are no Sundial snails or flat worms in there eating them away.

 

[rebelprettyboy]

How long have they been in ur tank???

 

[jwill275]

Using T5 lighting Nova Extreme Pro. Corals are halway up in the tank (125gal) I've been moving the Korilla 3 PH back and forth - up and down looking to see if it made any difference. I have 2 Korilla 3's and one Korilla 2 in the tank as well as the retrn from my filter. I am fighting a mild case of cyno bacteria and have been changing water about 25 gals per week. Using RO/DI with TDS readings of 0. I have reduced my feeding - I only have three fish - to once every other day.
Thank you

 

[scopus tang]

How big is your tank, and where are the zoas sitting in relation to the light? Maybe you have them getting too much light

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