Lost 2 fish in 24 hours ... No obvious explanation?

[trennamw]

Tank is 10 gallon, 1 month old, was cycled (quickly, with filter media from my 29) and then got a female betta and some crypts.

Last Monday I added water lettuce, Friday night I added 3 Otos. One Oto was dead Sunday morning, then the Betta died Monday evening.

Water tests are great, and unchanged after the Oto died. I found him quickly and the ammonia never spiked. Ammo/nitrite 0, nitrate <5, pH 7.5 and very steady, GH 7, kh 4. Water gets stress coat, and a small dose of cichlid salts and buffer since my tapwater is like distilled.

I'd suspect water quality if I'd lost another Oto, but since it was the Betta who went next I'm wondering if there's some quiet and fast disease I don't know about? Both Otos are still great.

Neither fish showed any signs of problems. Sudden death, bodies looked totally normal just pale afterward.

I hadn't changed the water in the past week, the temp is stable at 78.

I'm pretty new to all this but after learning a lot I have had a 29 gallon community tank doing very well for 2 months now (fully stocked, including the delicate Otos for past 6 weeks). And a betta who went into a 3 gallon very sick in February, who is happy and healthy and active now.

So is it a coincidence, or the next big thing I don't understand?

The only thing that makes me suspect the tank is I pulled a nerite from the 3 and put it in the 10, and it just lay on it's back for a full 24 hours, then has been active back in the 3. But the 3 and 10 get the same water.

[Delapool]

To me it looks good. Odd. Did you add many plants?

[UABsleeperSRNA]

that is very odd all your numbers look good.. just a couple of questions.. was it a new tank or used before you used it? if used did you use anything special to clean it? add any new decorations around the time they died? were both eating ok? were any chemicals used in the tank before you began to use it? it's odd for seemingly healthy fish to just die..? when you change your water how much are you changing?

[trennamw]

Things seem to have stabilized. I did lose another Oto but the third Oto is now at a few weeks and happy and healthy.

It was a new tank. Just rinsed it, rinsed the gravel, same as the other tanks I've started.

[absolutangel04]

Well, otos are notorious for dying off fast, even in a good tank. Also, anytime you introduce new fish, and then fish die but your water params are good, the answer is most often that something came in with the new fish that the residents didn't handle well. So, I would imagine the issue is not your water quality, but just the adding of the new fish. Also, bettas frequently die young due to long term issues from their handling before they made it into your tank. It is not uncommon for seemingly healthy, newer bettas to die off. I know it stinks though. So, I don't think your issue here has anything to do with your tank maintenance or water quality, I think it has to do with some unfortunate coincidences with your fish.

[Delapool]

Why are oto's so hard to keep? They seem to come up regularly on threads. I have an idea that are sensitive to nitrates (er, I think?) but they seem to drop off the perch at the drop of a hat.. Don't have them - just curious.

[treemanone2003]

Originally Posted by Delapool

Why are oto's so hard to keep? They seem to come up regularly on threads. I have an idea that are sensitive to nitrates (er, I think?) but they seem to drop off the perch at the drop of a hat.. Don't have them - just curious.

Through lots of reading about them, it's become my understanding that they are extremely sensitive since they are wild caught. They endure quite a stressful regime before winding up in a store and then eventually a tank. I've also read that it's best not to use a net with them but rather wait till they're attached to the glass and use a plastic cup or leave a cup with an algae wafer and scoop them up that way. The theory behind not using a net is the chance one of the mouth barbs may become stuck in it, tear off, and that will cause them to perish.


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[Caliban07]

Originally Posted by Delapool

Why are oto's so hard to keep? They seem to come up regularly on threads. I have an idea that are sensitive to nitrates (er, I think?) but they seem to drop off the perch at the drop of a hat.. Don't have them - just curious.

Apparently, a lot of it is to do with the way they are captured in the wild. I read and heard that a chemical/poison is used to force them to areas where they can easily be plucked from the water.

I'm not sure if they are farm bred but I believe the majority are caught from the wild this way. Then there's the usually shipping/handling issues and constant adaptation to different waters. Much harder to deal with when taken from the wild I would imagine.

[BBradbury]

Hello tren...

Small tanks need a lot of water changes, because there isn't much water to dilute dissolved wastes like much larger tanks. If you started changing out half the water every 2 to 3 days, the fish will likely be healthier.

B

[trennamw]

Our LFS Does list them as wild caught, I got this batch at PetSmart.

I've gotten two groups, and didn't lose any from the LFS group. Our LFS has quite the reputation, apparently, even across the country. It's a loooong drive across the city but I guess I'll stick with them for delicate fish.

Someone mentioned Otos eat biofilm, which is why I was thinking the tank wasn't mature enough. The point about the netting makes sense too.

The tank has never shown nitrates. I'd imagine there are big swings in total dissolved solids in their journeys, maybe they are extra sensitive to osmotic stress.

[trennamw]

Seriously fish speculates they get starved on their trip from Peru, apparently they need to eat pretty constantly ... And the mature tank is mentioned there too.

[Delapool]

Thanks My guide doesn't have much info on them. A mature tank makes sense. I'll have to see if the lfs stocks them out of interest.