Zoas

[bruce 1]

Everything in my tank is doing well except Zoas. I had several colonies that were about 500 to 1000 heads. The heads keep shrinking in size then just go away. They are under LED lights. And they did good for several months.
Could it be that the LEDs are to much light for them? All my LPS and Leathers are doing very good.

Then I have 4 RBTAs 2 are doing great and 2 look like crap.

All my water parameters look good. Water changes every 2 weeks (20%) I will try to post a picture in a bit.

Any thoughts on what might be happening?

 

[ringo®]

Could be the lights....any way to get a par meter? Could also be some type of predatory hitchhiker.

 

[eric b]

Probably not your lights as I have seen zoas under leds on a frag rack and were thriving at about 500-600+ par mid tank level and thrown on sand bed with about 200 par and they are still growing great. Been like that for almost a year now so I would say it is probably something in your flow or water quality even though you say params look great! Or you could look for some type of predator eating them!

 

[bruce 1]

I have looked for pest. Have not seen any fish nipping them. Water temp is 77.5 to 79.5.
Good test kits.
Going to retest in a few.

 

[ringo®]

Any type of algae outbreaks in the tank?

And when you say you've looked for pests, do you mean visual inspection or you've actually dipped them?

 

[bruce 1]

No Way to dip them. They are attached to 50 to 65 lb. boulders. The smallest rock I have in my tank is (I think) 35lb.
No Algae out breaks.

 

[ringo®]

Any white dots on the stalks?