Loosing fish dont know why

[gkersten]

I have a 200 gal reef tank that has been running for 3 months . Water conditions are perfect . Have not lost a single SPS LPS or soft coral since day one but keep loosing fish :cry:. I currently have a yellow tank , sailfin 3 clowns and 3 bi color dotty backs .

Any small fish IE Cardinals any wrasses, new clowns seem to last up to 2 weeks and then mysteriously go missing . No signs of the fish just simply gone . I thought at first the dottys were killing them off :twised:but they never show any signs of any aggression with during the day or at nite .

It was suggested that I may have crabs ( not hermits ) that came in the live rock that might attacking at a weak moment at nite when the fish are searching around . I have spotted a few 2-3 crabs about the size of a nickle that come out at nite and eat algae .

Any thougths:question:

[michika]

Post your specific water parameters, and maybe we can start there. Do you QT your fish? How quickly did you add all your fish? Was your tank set up from a previously existing system?

Can you list the fish that have died? In what order too if you can remember.

[gkersten]

CA 420 , mg 1320 , no3 no2 near zero . phos near 0 . Ph 8.2 Kh 9
temp stable at 77-78 f weekly 5% water changes .
185 gal tank 165 gal suno with refugium .
System set up form scratch 3.5 months ago
200 lbs live rock. shallow live sand bed with more live sand in refuge
Skimme rin sump ( euro 250) ca reactor , carbon 1 lb changed monthly in ractor tube .Hammer head pump for sump and dart with oceans motions recirc valve for recric and current within the tank total volume change near 8000 gal per hour . # 250 watt dohble end MH lights with 2 5 ft 80 watt vho for color . photo period 8 hours

Fish are kept in refug for 2 weeks . Added several fish at once to avoid any selectivity form aggressive species.
Lost 3 clowns on 2 separate occasions over 3 week period . Added 3 cardinals and a yellow wrasse at one time .They seemed compatible in the sump and did well for 3 weeks then slowly the cardinals would go missing one at a time over a period of 2 weeks . The wrasse I did not see after the 2nd day.

I would doubt it was water quality as all of sps etc are very healthy and growing.

[michika]

Nothing in your set up description sounds off, or the cause.

What about the SG of your system?

Was your rock dry or live when you put it into your system? Are all these fish from the same source? Right now I'm thinking; another unknown pred. you haven't seen yet, possibly infection/disease, or even residual cyanide effects that are just unfortunately hitting you all at once.

[gkersten]

Spec gravity is 1.025 . I cant figure it out either . Not all of the fish are bought from same store. My last addition was a yellow tang which is doing great 3 weeks strong eating well etc . What do you think of the crab idea .. ?? B.s or any validity . Do you think the dotty backs could be that aggressive when the lights go out . I dont see any aggression during the day

[michika]

I'm leaning towards a larger crab. Something you haven't seen yet. I'm thinking probably at least 2-3". Doubtful its the dottybacks if you aren't seeing any of this behavior when the lights are on. Since they are all from different sources, they have to be sharing something to make the virus/infection angel plausible, which doesn't seem so.

[Red Coral Aquariums]

Sorry to hear of your losses.

1) Your water parameters look good but just because your corals thrive it does not mean it is a healthy environment for fish. But your readings do indicate the acceptance for fish. Also they survived well in the same water for 3 weeks but in a different tank.

2) Losing 10 fish over a 3 week period ( if I am correct) could mean a few predators and an efficient clean up crew.

3) Could you list what inhabitants you have and what you have lost and when?

4) At what time during the 3.5 months were the first fish added and inverts added etc.

Here is a few known points and a few questions. I have a feeling it is a mantis or a few bad crabs. Keep us posted and consider a trap in the meantime.

Good Luck
Kevin

[gkersten]

I think my best option at this point since I am not going to change the water conditions is to set a trap and see what I catch :twised:

Ill keep you posted

[Keri]

You'd be suprised what you can find hiding in 200lbs of LR....even months and months later. It could be a larger crab or even a mantis.


You should try spotlighting a bit late at night with a flashlight, see if you can see anything funny.

[Whatigot]

I picked up a blue led flashlight that is ultrabright but does not seem to scare my tankt he way a white light does.
it works really well for having a look at my pistols and crabs at night, I caugt one crab that way.

[Myka]

I'm thinking it's a mantis or pistol shrimp. Do you hear any "clicking" at night particularly when the lights first go out? I had a mantis in a 33g tank for 8 months before I found it. There was a 3" crab in a friend's 180g tank for over a year before he found it. So, sometimes things hide VERY well for a LONG time!!

[Bryan]

Used to have the same problem, until I came home one day and noticed a Mantis shrimp scrurrying across the sand. He had been there for years and I had no clue, every once in a while I would hear a click but attributed it to a snail falling off the glass. Took me a long time to find his lair.

[gkersten]

Thanks for the replies . I have set a trap and will see what happens.

[Bryan]

Never had any luck with a trap, I had to pull out each and every rock and inspect it to find it's "little nest". And as luck would have it, it was literally the last rock I pulled out in the tank where he was hiding.

Hope you have better luck<g>

[fishytime]

I am thinking that perhaps the fact that you have put a large bio-load in what is basically a brand new set up may be your issue. What brand and how old are your test kits? Have you taken a sample of your water to your LFS to confirm your readings? If your problem started more than a month ago that would mean your tank was only two months ish old, which is fairly new to be adding that many fish at once. It is possible that your fish are dying from water quality and your clean up crew are taking care of the carcass.

[Evil Guppy]

I would echo what many others are saying about a crab or mantis shrimp as I had the same issue when setting up my tank a few months ago.

I had about 70lbs of liverock in a 90 gal tank and 5 chromis. All fish seemed healthy but every couple of nights a fish would disappear by morning. I could never find any of their bodies.

One morning I checked the tank and found a dead Gorrilla crab. I figured that it was the cause of all my problems but I kept losing fish after that. I ended up finding another 3 pretty large crabs after that.

So as others have said you could have alot of crabs in the amount of liverock you have as I had at least 4 with only 70lbs of liverock.

I didnt use a trap for the crabs but i did find that when i fed frozen brine shrimp, i could see crab claws coming out of the rock trying to get the food. I then was able to pull the live rock out and use tweezers and a screwdriver to push the crab out.

[naesco]

Just want to confirm a few things.
1. Have you lost any tangs?
2. When you say refugium do you mean Quarantine Tank (QT?) which is a tank completely separate from the main tank.
3. Using a flashlight do you do you see any salt like spots or any whiteish coating on any of the fish?
4. Are you adding any additives to the tank?
Thank you