Please help losing fish daily!

[mschum]

Hello Everyone, first poster, long time lurker having problems with tank. Here's my situation.

I’ve had three fish disappear over a three day period, one fish per day. The first fish to go was a citron goby. The goby had started to look weaker over the past few months, and wasn’t eating ferociously but I couldn’t find anything really wrong with him other than being skinny. So I wasn’t terribly surprised when he went missing. The next day my female black false clown of the pair disappeared. This fish was healthy, good eater, and quite a bit larger than her mate. The following day my male orange false clown in the pair was gone. Again, he was healthy and a good eater. Now I am starting to suspect that there is something else going on in my tank when the lights are off. I just installed a trap to see if I can catch anything overnight. Here’s the rundown…..
History:
90 gallon tank (and 30 gallon sump) has been up and running since March 2010.
After going on vacation in September I had a recent green hair algae outbreak, and I was out of GFO so I had to order more. The green algae is starting to die off and the phosphates are coming down. Fish have been on reduced feedings since algae outbreak. I’ve also been leaving the lights off during the day to help with the algae, and the fish seem to be disappearing during these dark periods. My wife works from home and watches the tank during the day and she hasn’t been able to find any bodies (or parts).
I also have been fighting a small aiptasia infestation for awhile. The only thing that really kept them in check was peppermint shrimp, but I kept having those disappear on me too (about a dozen). I then noticed that my blue-eyed cardinal fish had a shrimp hanging out of his mouth one day so I banished him to the sump. I bought six more peppermints after that and they didn’t last very long and it didn’t look like they ever touched the aiptasia.
I have also had a couple mechanical problems in the past few weeks. My skimmer has been acting funny and keeps overflowing (coral life super skimmer). I suspect the skimmer problems could be do to the algea. Yesterday I lost one (of my two) Koralea powerheads(cracked the magnet and stopped working) but I will be replacing that tomorrow morning.
Current levels show:
Salinity - 36
Total Ammonia - 0 (Salifert test kit)
Nitrites - .05 (Salifert test kit)
Nitrates - .10 (Salifert test kit)
Phosphates - .07 (Hannah checker)
Calcium - 400 (Salifert test kit)
Alkalinity - 10.5 dkh (Elos test kit)
Currently has the following inhabitants:
80 lbs of live rock
1 inch layer of aragonite sand
1 Yellow Tang
3 Green Chromis
2 Threadfin Cardinalfish
1 Blue - Eyed Cardinal fish (in sump - not main tank)
1 Queen Conch
3 Small Hermit Crabs
10 Astrea Snails
Stunner Chalice
Green Favia
Red Favia
Fiji Yellow Toadstool
Trumpet/Candy Coral
Green Palys
Hammer Coral
White Toadstool
3 Zoa Colonies
Green star polyps
Carnation star polyps
2 birds nest
Other:
3% Water changes daily
Running ¾ GFO in a filter sock
1 functioning Koralea powerheads
Small amount of slime algae (not taking over)
Small amount of red hair algae
Any help…ideas…or advice would be greatly appreciated. Please let me know if you would like anymore information.
　
　
Thanks,

Mark

 

[miami dolfan]

Those cardinalfish can get pretty mean. Good move in taking him out.

 

[dawgface]

Hmm stray voltage

Mantis shrimp? Have you added any rocks or anything where one could gave hitch hiked

 

[smoothie]

Check for stray voltage. Make sure you aren't starving the fish. A little twice a day is better than a whole lot twice a week. Regular water changes of course

 

[mschum]

The clowns ate ferociously at a minimum once daily mix of pellets/flakes and two to three times a week frozen mysis/brine. I will check stray voltage tomorrow. I also forgot to add i checked overflow and they are not in there. No rocks added within 1 year. Cardinal has been in sump for over a month so he is not the culprit.

 

[irahmatulla]

Would Mantis harm fish? I assume that would be a good loss of shrimp, but I have only seen them attack crustaceans. If you skimmer is overflowing, there is a possibility that gunk is spiking in the system, and then tapering off. Could this be a possibility (from more experienced reefers please chime)? Also, is Alkalinity another form of measuring PH?

 

[smoothie]

IRahmatulla;702106 wrote: Would Mantis harm fish? I assume that would be a good loss of shrimp, but I have only seen them attack crustaceans. If you skimmer is overflowing, there is a possibility that gunk is spiking in the system, and then tapering off. Could this be a possibility (from more experienced reefers please chime)? Also, is Alkalinity another form of measuring PH?

They will consume/kill anything they can catch. They are true fatties like me

 

[irahmatulla]

Aw beast! I need to get me one of those. Ok, then if that is the case, how intricate is the rockwork? How much rock do you have? Is there a possibility that you got one, and he has grown over the last year or so? Ever hear loud smacking coming from the tank?

 

[dakota9]

Gorilla Crab?

Mysterious

 

[jennm]

Blue-eyed and Threadfin cardinals are the same. Apagon leptacanthus (P. 146 of Scott Michael's Pocket Expert Guide to Marine Fishes). They aren't a threat to fish or sessile invertebrates.

Perhaps you have a different specie? Pajamas and Banggais can be a threat if they're large and the crustaceans are small.

Nitrite in your parameters? A long-established tank should have 0 nitrites, and even if there was a body or two decaying in there, they are so small and the water volume such that you shouldn't even see a blip. I'd suggest double-checking that.

If you aren't finding bodies, it's likely that you have some sort of predator in there. Might be a mantis shrimp, hitchhiker crab... something that came in on your rock when it was tiny, now that it's grown some, its appetite is bigger (esp. if you've cut back on feeding and there's not as much to scavenge).

Voltage is a possibility, but IMO it's more likely that you've got an unwelcome guest.

Jenn

 

[rdnelson]

Very new so take what I say with a grain of salt but....I have read that flake food is notorious for adding phosphates to the system. I know it isn't your main concern but you mention you have a bit of an algea problem. Could that be the cause?