Fish deaths

[Jarob]

Alright this is the second fish that has died in my tank in the past week. First was a six line which was in my tank for over a month, healthy as can be and eating like a pig, one morning I woke up and it was dead. Today I woke up and my blue damsil was laying dead, he was only in the tank for 2 days but was eating and appeared healthy. Each fish was the only one in the tank at the time too. Ive got a 20g long with mag 9.5cl w/scwd, HOB fuge, carbon, 1x24w actinic, 1x150w HQI 20k, about 60lbs LR and 40lbs LS, mangroves, cheato

ALL my corals are doing GREAT with amazing color and polyp extension, even on my two SPS frags. my GBTA is doing good but not bubbling up as much as I would like but has a nice tight mouth, coming out when the lights on and is showing good color and everything.

Params are as follows for the last 2 weeks:
Saturday, March 21
KH = 197 ppm
Calcium = 475 mg/L
Nitrates = 0
Nitrites = 0
Phosphates = 0

Saturday, March 28
KH = 11dKH
Calcium = 540
Nitrates = 0
Nitrites = 0
Phosphates = 0

Im using a reef master test kit to test. Water changes are about 25% give or take every weekend, and the tank is topped off with fresh RO. I dont over feed as I had only one fish.

Any suggestions/reasons/thoughts?! Its really bugging me and I can not figure it out for the life of me!

Thanks,

Jarob

[sharkboy]

how long has the tank been up?

[Jarob]

4 months now, all previsouly set-up water, lr, ls. already gone through all cycles

[Gilbert]

what about salinity and temp?
do you have a powerhead on a controller maybe the fish go in when its off them get chopped up when it turns back on?
any damage on the fish like scratchs or cuts? maybe a hitchhiker

[gjuarez]

If all parameters are in check, you can also check for stray voltage

[Jarob]

Salinity is always around 1.024-1.025
Temp stays between 78-80

My assumptions are leading to a hitchhicker as both of the fish had a little eaten out of them by the time I got to them, something must be nipping at them at night.

Tonight, I'll keep my eyes pealed for a hitchhicker with red lighting.

[Jarob]

Found two culprets lastnight! A rather large moon snail I forgot I put in the tank when setting it up and nothing else was in it, not a good idea, and some type of small crab that must of hitchhicked his way in. Ive seen the moon snails eat anything in their way before.

[Jarob]

Problem solved: Took my heater out of my tank, must have been leaking current in the tank. Everything is doing GREAT now! Thanks for the help.