Mysterious Sudden Clown Deaths...please help

[tommydee]

1st, very grateful for finding this forum, has been helpful....but grim news that I need help diagnosing . Both of my false perc clowns (4 months in the tank) started swimming in circles night before death...next morning, one turned white, other couldn't stay off ground...had eaten the day before...did not appear to be ich or brook, but had to try something

Ran out to buy copper, got back, both on sand...at this point nearly dead, I easily netted into a copper bath (5 gallon water change bucket), with my filter running (no carbon). Went out for an hour, not surprisingly, both fish dead. ONe white, other normal...both had purple just ahead of their tail fin, like internal bleeding. This happened extremely fast, within 24 hours.

2 days later, my 3 hermits, pistol,Yellow watchmen goby, and small mantis are totally OK and normal. (except 1 slow hermit who has been near death for about a month). Did 30% water change this AM, probably another in 2 days.

I have a 29 g FOWLR, about 15 lb of live rock that has been rock solid for 4 months since cycling. (Just ordered skimmer, being shipped and shopping for lights to consider BTA addition )Just checked water night before death, parameters were good.

Tank info
29 g FOWLR, 15# live rock, aquatech 20-40, cheapo lighting, no heater.

Chemistry
Natural reef water (Puerto Rico), diluted to 1.023 salinity w/ dechlorinated water, 20% change every 1-2 weeks, temp ~82 F

Predeath (day before scheduled water change)
Ammonia 0 (always)
pH 8.1 (always)
trite 0 (always)
trate 5-10 ppm

Post death: same, but for first time in 4 months, the ammonia test was between 0 and 0.25 color...maybe a spike?

Theories

1. My wife puts natural seaweed in every now and then from the local beach, so I closely monitor for die-off spikes...maybe one had a strange parasite, or my water testing missed a spike? (this will be forbidden moving forward!)

2. I have 2 hitchhiking mantis shrimp, but they are small and have yet to even hurt my CUC...doubt one would attack 2 clowns

3. Freak parasite from local seawater? But if so, i would expect this AFTER a water change.

4. 1 week ago, wife/kids put in small, white rock found at beach w/ little sea urchin on it, just washed ashore...maybe it had a toxin/bacteria?

Just did water change now. I am planning on closely watching the last fish standing (YWG), and assuming a 6-8 week monitoring period, with skimmer up and running before putting some clowns back in.....this was a lot more emotional than i thought it would be, and my kids were a mess

Any feedback on what went wrong would be appreciated so I can prevent another mishap.

 

[tommydee]

Update on some omitted information---2 additional theories I would like to ask the experts to consider:

1. I replaced my aquatech carbon just 1 night before this started. rinsed thoroughly w/ tap water before insertion...but not dechlorinated...crap, hope this didn't do it.

2. Other theory is I do have a closed hood, and had not changed water in 2 weeks. While my LR has demonstrated good biofiltration, and I generally have low bioload, maybe not enough O2 in the water with my powerfilter? The YWG is much more mellow, so perhaps not as affected by low O2?

3. After 30% water change, took readings, and again, ammonia showing 0-0.25 ppm color...not the typical "dead 0" I am used to...so ammonia spike perhaps still ruled in.

Thanks for any help, this is driving me a bit mad.

 

[Conrad25]

Doesn't sound like ammonia if your watchman made it thru along with the CUC. Sounds like it maybe ate something as none of the others were affected.

 

[tommydee]

Several days later update: yellow goby and cleanup crew totally fine, water parameters all OK (nitrate around 5)...Protein skimmer should be here any day...this is still a mystery, but I guess sometimes fish just die suddenly for no reason?

 

[WDLV]

I like the disease theory. Especially brook. It doesn't have to be visible on the skin to affect the gills and clowns are highly succeptable. All it would take is one wet thing not being quarrantined.
I like the dissolved O2 theory second best. Especially in the AM when the levels tend to be lowest.
I like the mantis theory too. Especially since you saw what looked like injuries. They like fish. Especially if the fish were aggressive with it and we all know clowns are very territorial.

 

[tommydee]

Thanks WDLV. I want to resolve all possibilities before replacing the clowns, don't want to be a fish-killer. The skimmer will take care of theory 2. I'll do more homework on brook to find out earliest I can put in new fish, keeping in mind the YWG is healthy as can be.

I guess the lesson is to be a responsible clown owner, I should buy formalin just in case + 10 gallon QT that I can quickly transfer to in a matter of hours at first sign of brook. And I have a tiny baby mantis, and just found another one, but the largest is less than an inch long. I guess I need to exodus them?....I thought they would mess w/ my CUC before clownfish.

Any other opinions on the Mantis theory?

 

[RcToners]

Where are you located ?? Cirolanid isopods are very common hitchhikers where I live and could have easily been the cause.

 

[tommydee]

Puerto Rico....very possible

 

[slosht]

In my experiences with my 2 mantis shrimps, when they kill a fish I wouldn't find the body as they tend to bury or hide them. If/when I was able to see a body, it was partially eaten.

 

[tommydee]

after doing homework, don't think it's cirolanid, would have seen these on the fish, or in the tank at night. Agree w slosht, my mantis are very small, and I would think they would mess w the goby or the 4 hermits before 2 clowns....Must be brook, or other strange parasite/toxin...I will assume brook so I'm ready for it next time. Nothing enters without QT first...I'll run the new skimmer for 2 weeks, then drop in another pair of false percs, I guess.