[RDonald]

Hi Everyone,

For some time I've been wondering if my Oto's are okay, I have six of them in the 25g, heavily planted with diy CO2, ammonia, nitrites, nitrates all at unmeasurable levels with my test kit. Ph hovers around 6.8.

The oto's quite simply all sit attached to the glass and the heater behind my forest of stem plants and rarely move. They all seem to have plump bellies and aren't showing any outward appearances of sickness, they just don't move around at all. The other fish in the tank, tiger barbs, neons, and corys all seem healthy and feed well. I'm wondering if they have just found themselves a nice comfortable spot with enough algae to graze on without having to move at all. (I have had an algae outbreak recently but its slowly being eradicated with a change in lighting cycle and fert dosing changes)

There was a time when they would swim around the tank and do their thing but its been about a month since they have gone into "hiding." I've had them for 4 or 5 months now so it isn't acclimitization and my tank has been stable for as long as I can remember. Am I just being a worrier?

Thanks!
Ryan in Richmond

 

[Scholz]

Ever check on the tank in the middle of the night?

 

[Morainy]

I've noticed that otos can slow down their activities for 2 reasons: There's more algae in the tank for them to feed on, or there's a bossy fish who keeps them in line.

Were your otos more active when your tank was new and algae-free? If so, then the recent outbreak of algae may be to blame, as you suspect. They probably feel like they're at an all-you-can-eat resort. Or, have you added a new fish to the tank? Or removed a fish?

The otos in my female betta tank have been less visible since I removed two juvenile rams from the tank that my female betta was enjoying keeping in check. She wasn't biting them or anything, just running at them from time to time. While they were there, the otos had the run of the tank. Once they were gone, they began hiding from the betta because from time to time, she'd chase them. Nobody's getting nipped, though.

I also notice that the otos move around the tank at night more than in the daytime these days.

 

[RDonald]

I've checked at midnight, which is more than three hours after the lights are off and have looked at six am which is four hours before the lights come on and they are always in the same spot. The four smallest ones almost never seem to move. The two largest guys (or gals) come out once in a while but they always seem to retreat back to that same area again. Several months ago they were quite active, spent a lot of time swimming around, even interacting with the other fish in the tank or schooling as a group. I have tried luring them with algae wafers at lights out time, but several hours later I just end up with piles of mush so I gave that up, I guess the real thing is better than processed.

 

[Scholz]

feed them any veggies ever?

spinach lettuce zuchinie?

 

[Morainy]

Maybe they're okay, and you're just worrying.

Maybe, given their rotund tummies, they've been pigging out on bloodworms meant for your other fish and have to snooze them off? Or, has the temperature in your tank changed? Maybe they're quieter in cooler water.

I am obviously just guessing. I hope that your otos are healthy. Over the years, I've noticed that some groups of otos are lively and others are quieter. Maybe hanging out on the wall is a sign of contentedness in an oto?

 

[Theratboy_101]

I have 3 in one tank and I almost never see more then one at a time in the day till just before I turn the light off then I’ll see two.

One of them (the big one) I'm lucky to see at all! It hides most of the day coming out maybe once or twice but go’s back to hiding right away. But after I've turned the light out it comes out and rules my tank at night!

 

[vcat]

i had that problem before too. i had 4 in a 6 gallon and i hardly ever saw them. definately more active once the lights were out, but not by much. then i moved them into a bigger tank and they actually spawned. now they're in a bigger group of otos (12 in each of 2 tanks). a few will be a little active even with the lights on. but some never come out at all until the lights go off. but i think the bigger group helps.

 

[RDonald]

I don't think they are being bossed around, before they went into their permanent siesta they would spend large amounts of time chasing around in the filter current with my school of tiger barbs! The barbs actually bump them with their noses now and then and they don't even move. I have lowered the temp by 2 degrees over the past month, I found that it was creeping up over 80 during the daytime with the lights on so I moved the heater temp down a couple of notches and managed to get my daytime temp to sit at 78-79, at morning time just before lights on it is at 76-77. No changes in the other residents of the tank in the past few months.

It sounds like this kind of sedentary behaviour is normal, I had considered moving them all to my 55g but I can't really justify changing their environment if they are comfortable and happy. I'll just keep watching them and doing my daily count to make sure they are all there and see what happens as the algae slowly goes away.

 

[jobber]

i have 1 in my 6 gallon tank and it does an immaculent job in maintaining my algae. mine isn't afraid to come out and is quite active. i think why your's are inactive is that there's no competition for food and they can just relax. i'm sure they are fine since they have plumb bellies.

i have tried to introduce another 3 but they compete with one another for food so stressed to death. so i resorted to corydoras.

another consideration maybe that they've just laid eggs and are recovering from all the extracurricular activities during the night.

Oto's are awesome. you see the video on youtube where they catch them in the wild: