These guys are great. I used to have 5 of these spectacular fish but now I only have 4. I never did find out what happened to the other one. Mine live with 3 Platies, 2 Bronze Cories, and 1 Harlequin Rasbora. They all live great together!
I had 10 of these in a well planted 110 L tank with 7 silvertipped tetras and some other fish. The Silvertips were too aggressive and I moved them to another tank and bought 2 more X-Rays and 2 Ram Cichlids and an upside down catfish. Now everything is in perfect harmony. The X-rays school in a loose formation, while the 2 Rams swim around and hang out near the driftwood, rock caves and clumps of plants. I have a CO2 system and keep the water by doing partial water changes 1-2 times a week and use the old aquarium water to water my plants.
The 3 I had in my tank were as mean as can be to my other fish - especially my bettas. I had my red betta in my 40 L tank with the prissys and the first couple days I noticed that the betta's fins looked a little tattered. No worries says the wife, betta fins just split sometimes. The next day the fins were even smaller. So out comes the betta into its own 8 L and the pristellas are on their own. Several weeks later some fire platys were introduced. No real trouble there - or maybe no temptation to eat fins. Then I bought a blue betta to add to the pristella infested tank. "That won't be a problem, unless it's the betta being aggressive" - the fish store lady assured me. Well, two weeks ago the pristellas chased the blue betta into a corner, where he tried to hide in some rocks, got stuck and his fins were all chewed completely away. He died within 48 hours despite being moved to a solitary tank to attempt a recovery. Needless to say, no more pristellas, ever.
I recently added 6 of these great little swimmers to my tropical river styled community tank. They settled in nicely straight away and seem to school really well. Sometimes they school tightly, but sometimes loosely depending on if other fish are about. When feeding time comes they don't hesitate at all. The leader of the group (who is substantially bigger) will eye up a flake at the surface and the group will shoot up like torpedoes, grabbing the piece then shooting down. The group will then demolish the flake in seconds. Very nippy fish, very entertaining to watch. They seem to get along very nicely with my two clown loaches I just added and they share the feed well. No aggression towards each other, if you didn't know otherwise, you'd say the two species were working together. Great fish, very hardy, a big recommendation to any aquarium lover who wants a beautiful, active fish
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