[dwref]

I am losing fish fast.
My tank is a 125 soft tank. Heavily stocked.
I have a 30 gallon sump. SWC Skimmer.
My tank parameters are
Nh4 = 0
No2 = 0
No3 = 0
Alk = 12.8
Cal = 450
Mag = 1350
Po4 = 0
Temp = 79
Ph = 8.3
Saly = 1.026

Over the last month I have lost, 3 Angels, 1 Cleaner Shrimp,
2 Clown Gobies.
I still have 2 Black Clowns & 1 Yellow tang. They seem to be fine, but don't want to lose them.
All my snails & hermit crabs, as far as I know are doing OK. Can't see them all.
All my corals are doing fine. They come out everyday. I do a 15 gallon water change a week.
I run my lights from noon until around 11:00 pm.
I have 3, 250MH, 20k.

Thanks

 

[drhank]

It sounds like you are doing everything right. Are there any signs of fish disease. I suspect no. Honestly, I'm thinking nocturnal predator. Try checking the tank out with a red light after dark and see if you see anything. Also try a clear glass, tilted on its side at a 45 degree angle, baited with a grocery store shrimp. Put it in the tank just before lights out and check it in the morning.

I'm thinking gorilla crab, especially if you managed to get any Tampa Bay live rock in your tank. Good luck.

 

[JA McDougall]

Alk looks a little high...Im thinking get it under 5 and see what that does

 

[ltownsalty]

Dr. Hank, I just recently saw something very similar to the gorilla crab in my tank the other day after buying a new piece of live rock for my tank. I had one of my hermits die very unexpectedly today after no signs of stress or disease, everything else in my tank is flourishing finally and am kind of curious if that might have something to do with what happened

 

[dwref]

It sounds like you are doing everything right. Are there any signs of fish disease. I suspect no. Honestly, I'm thinking nocturnal predator. Try checking the tank out with a red light after dark and see if you see anything. Also try a clear glass, tilted on its side at a 45 degree angle, baited with a grocery store shrimp. Put it in the tank just before lights out and check it in the morning.

I'm thinking gorilla crab, especially if you managed to get any Tampa Bay live rock in your tank. Good luck.

No idea of what a "Gorilla crag" even looks like.
I will try the store shrimp, but I am almost sure that I do not have one of these in my tank.

 

[dwref]

Alk looks a little high...Im thinking get it under 5 and see what that does

I understand what you are saying, but I have about 17 fish that are fine??

 

[dwref]

Dr. Hank, I just recently saw something very similar to the gorilla crab in my tank the other day after buying a new piece of live rock for my tank. I had one of my hermits die very unexpectedly today after no signs of stress or disease, everything else in my tank is flourishing finally and am kind of curious if that might have something to do with what happened

There really isn't any way for a crab like that to get in my tank, I have not put any new live rock in it for probably a year now!

 

[dwref]

Just wanted to say "Thanks" to everyone that replied!