Oto Cats dying mysteriously

gerilyn · Post by **gerilyn** » 07 Apr 2007, 05:55

Added 5 Oto Cats to the tank Feb 9-10. They've been fine, I thought. Other fish are fine and no other fish added recently.

Suddenly, they're dying. The first died Mar 23, then Mar 27 and 28. I added squash in case they were starving - the Corys and Danios like the algea tabs too - and I've seen the Otos go after squash and brocolli with gusto.

I lost the 4th Oto tonight, right in front of my eyes for no apparant reason. I was watching the fish after feeding them. The Otos were sucking on the glass as usual. One of the Otos suddenly sank to the ground; he tried to swim again but couldn't; he kept sinking back to the ground belly up.

Obviously he must've already been sick, but of what? He looked fine until suddenly he wasn't. They all looked fine until they were dead. No autopsies, of course, but they look fine (not sick) deceased too. The last Oto looks fine.

The water chemistry is fine, and has been. I haven't detected ammonia or nitrites since Feb 26. Nitrates have never been over 20.

Post by **Shane** » 07 Apr 2007, 06:26

You are not the first person to have this problem. Starvation is the most common cause of Oto problems. How long were they in quarantine? I have found that Otos, like Farlowella, often need several weeks without competition to regain their strength and put on some weight. If all the other tank inhabitants are fine then starvation is probably the most likely reason for their demise. I would say this is especially likely as they all kicked off, not at once, but within a few days of each other 5-6 weeks after purchase.
-Shane

gerilyn · Post by **gerilyn** » 07 Apr 2007, 16:03

I confess I don't have a quarantine tank. I feel just awful about this.

How can I feed the Otos more? Like I said, they eat squash and brocolli and skinned peas; the other fish like the brocolli (the danios wind up tossing it all over the tank), but Otos didn't seem to have to compete for the squash, which they appear to like.

Also, my tank has no sunlight, only the tank light; there's no visible algea growth at all (if any algea has grown, the Otos got it).

Can I just keep feeding the Otos more squash and peas?

What about seaweed, the kind that clip onto the side of the tank?

I could also add a live plant; are any of the plants sold okay, or do you recommend a particular type?

I've also thought about growing algea in a glass in a sunny window sill.

Post by **Marc van Arc** » 07 Apr 2007, 18:07

gerilyn wrote:I could also add a live plant; are any of the plants sold okay, or do you recommend a particular type?

Vals (Vallisineria) are highly recommended: they look well and at least my Otos sit on them all day.

gerilyn wrote: I've also thought about growing algea in a glass in a sunny window sill.

Put some stones in it, place it somewhere sunny and within no time you'll have plenty of algae.

Mike_Noren · Post by **Mike_Noren** » 07 Apr 2007, 19:29

Squash and peas sounds good.

Since your otos are eating (check if they have insunk bellies or not - a healthy oto has a little 'beer belly', whereas a starving oto has an insunk belly), it'd seem as if disease or poisoning are the most likely causes of death.
Have you medicated the tank recently? Water quality is good? Any visible symptoms at all on the otos?

Hell Fire · Post by **Hell Fire** » 07 Apr 2007, 21:01

They are delecate and the slightest tank changes at 1st can take them unfortunatly. Im lucky and all mine were fine and have been since i got them last year in the summer. Mine have a feast of cucumber, algea and bottom tablets along with anything else. There rather fat and am hopeging for them to breed. I keep my tank in optimum condition, its hard work but the waters got to be great for them to live. So many people loose them even if the other fish are fine, its just them, as said thier so suseptable.

gerilyn · Post by **gerilyn** » 07 Apr 2007, 21:36

Ammonia and nitrites are zero, nitrates are less than 5.0. I've never medicated the tank. No visible symptoms of illness, that is, nothing that looks odd or out of place (I don't actually know what the various fish diseases look like).

One of the dead Otos was missing fins, but I'm pretty sure that happened post-mortum. The other dead Otos were completely intact, and I saw the other fish started picking at the one last night after it quit trying to swim.

Their bellies aren't sunk in, but they are clearly not as fat as they were about a month ago. Fish-keeping newbie, I was overfeeding everyone (all the Otos had bellies, and the danios got so obscenely obese they looked almost square in appearance). Since I had ammonia-nitrite issues in February, I've been less frequent about my feedings (across the board including algea tabs and squash) so it probably is starvation.

I'll keep a constant supply of squash and peas in the tank. They have to compete for brocolli. I'll try a live plant (Vallisineria, I suppose); we'll see how the plant does in artifical-only light. I'll grow algea on rocks in a window sill and rotate them into the tank. And I'll watch my remaining Oto for weight gain.

bronzefry · Post by **bronzefry** » 09 Apr 2007, 22:06

When I started with Otos, I got two groups. One was from a local store. I also got a dozen from an internet retailer. I thought the ones I bought locally looked good, but the ones that came from the internet retailer looked great. You could see little bellies on them. One month later, all the locally purchased Otos were dead. The ones purchased from the internet are currently mangling some zucchini in a 75 gallon tank. I purchased them two years ago. I still want to set up a 10 gallon planted/breeding tank for Otos. But, I seldom see tanks locally with nice looking Otos. They look starved. Maybe I'm going to the wrong store or something.
Amanda