BTA shrinkage :(

[sfarid123]

Hi guys,

A few months back, I had purchased a large & healthy GBTA for my 55g mixed reef tank. My concern is it has slowly reduced in size since I purchased it and has gone from 8" to 4" in diameter in a matter of 6 months.
I feed it diced shrimp, silver sides, formula 1 , once or twice a week.
I also have a 4" perc that refuses to leave the BTA.

Physically the BTA looks fine, no bleaching no gaping mouth, but the tentacles that used to be 6-7 " long have gone down to 4" :(

What is causing my BTA to slowly reduce in size??
What should I be doing so I can keep her nice, big & healthy??
Thanks.

Parameters:
PH 8.4
Alk = 13 dkh
Salinity 1.25

NH4=0 NO2=0 N03= 0.5 (**do not have a refugium)
PO4=0

Aquac remora Mag3
Light 4X T5 SLR

[garygb]

Could there be another coral/anemone (i.e., cnidaria) that might be engaging in chemical warfare with the anemone?

[sfarid123]

I am running activated Carbon as well to eliminate the possibility.
My reef consists of mainly mushrooms. Also the BTA does not have any direct contact with the corals.

Thanks.

[rssjsb]

Since you're feeding it (the usual suspect when anemones are losing tentacle size), I'd say it could be the mushrooms, or other soft corals that you may have (like sinularia or colt corals).

How often do you change your carbon?

[garygb]

Activated carbon and protein skimming should help some. I've read experts advise small weekly changes of activated carbon.

[Grunt]

What's tank temp?

.....and when's the last time you fed? It might be expelling waste.

[9501gle]

Why dont you try feeding it more and see what happens. If its not hungry it will just reject the food anyway.

[sfarid123]

I change my carbon once a month using the TLF phosban reactor.
I keep temp at 78.
Also I thought for larger nems you should only feed it once a week.

Do you suggest doing more carbon change/week?

[rssjsb]

I think mushrooms are pretty nasty in the alleopathy department. I've also read that carbon loses its capacity for chemical filtration pretty quickly - like in a few days. (Don't know how accurate that information is because I can't even remember where I read it, but it's consistent with garygb's advice above.)