Hi everyone,

I have 2 oscars (one black, one albino), and a small shoal of silver dollars in my 150 gallon tank. I've all them all for about 6 months now, and for some odd reason they all like to huddle in the same corner of the tank! Despite the vast amount of swimming area available, the silver dollars and the oscars keep calling the same corner as their "base". I've seen on several occasions where the black oscar would try to take a bite out of a silver dollar (they are way too huge to be swallowed (4"), but I'm sure it could latch its mouth onto a silver dollar sideways. Yet, the silver dollars continue to swim around the oscars like they are best friends. I'm pretty afraid that one day the oscar might kill one of the SD, but overall the oscars seem pretty tame.

How do I encourage either the oscars or the silver dollars to move into another part of the aquarium? I've tried rearranging the rocks around many times and it has failed.

EDIT (additional info): The black oscar does wander around the whole tank occasionally, and the albino oscar always cower in fear whenever he sees the black oscar coming towards him.. YET it still stays in the same corner as the black one!!

Also, I'm pretty disappointed that the fishes don't swim too much.. especially the silver dollars. They just seem to want to stay in the same corner of the tank all the time. I do water changes weekly also regularly check the water parameters which are in the appropriate ranges.

I have SD that won't stay still, my O's can be lazy at times and they do have special sleeping places but I've not heard of this problem before. The mods will be waking up soon and will have some great ideas I'm sure. Have they always stayed there?, it's not a recent thing?

Sinstinna wrote:


It's not a recent thing

When I first got them they were swimming more (6 months ago). The SD's use to swim from one side to the other when they were tiny... but now they just huddle in the same corner and swim in that small area. Most of the time they are just idling.

When I feed them though, they would be very active, but they would still only stay on the same side of the tank.

SD's can be easily spooked, is there a lot of activity around the tank? That would explain them but not the O's, in my experience the more action the better they like it.

How many SD's do you have? They do best in schools of 5 or more, maybe there's not enough for them to feel safe moving around.

when i overstocked my community tank the different breeds would huddle together and not move much..

but you have 150 gals so that shouldnt be a problem

The tank is in the large living room and there is little noise and activity that would spook the fishes. There's a total of 6 silver dollars and they huddle together like best friends.

I just find it really odd that all the fishes are calling the same corner as their spot. It is because the heater is there? It is set to 78 degrees.

They'd hang around the heater if the rest of the tank was cold...I think...I'm interested in what the others have to say about this. I like new problems but I'm not always good at solving them ...We'll figure it out I promise!

is the tank cold to touch?

if its cold to touch it might be too cold

my fish always hang around the heater after a water change... i know i should put warm water in, but it dosnt bother them much

Don't give them too much of a shock when you do a water change, it will stress them at the least and could hurt them.

unlimitedx wrote:

please check if the area where they usually stayed:
1)is it the discharge point of your filter pump?
2)is it near the thermometer?

there must one reason why and you have to find it..
may be there is something keeping them not roaming around..