Tiger barb issuesssssss?

i have a 20 gallon tank with a convict, a adjectives pleco(will get moved to a 55 when it gets 11 inches) and 3 tiny tiger barbs, they other nip at each other, is that normal?, how many barb can i keep in my 20 gallon tank whether this school isnt big enough? what can barbs guzzle apart from flakes?
I think you should move the pleco a little sooner then 11 inches. He might not even attain that big in a 20 gallon tank.

A convict will need the 20 gallons to himself. They can find territorial and mean.

A school of 3 barbs will produce issues. They should be in groups of 6 or they'll nip.

Other things that can be fed to barbs are freeze dried bloodworms, freeze dried shrimp, frozen brine shrimp, or verbs and finely chopped earthworm from outside. (If you don't use chemicals in your lawn)
Tiger barbs need to be within groups of no less than 5, any less and they will nip fins, tiger barbs chase respectively other around all day and eat, and thats it. When theres too few within the tank they end up chasing other fish around usually end up in nipped fins. Tiger barbs are a correct community fish but when kept in groups too small they do that, its totaly normal, just donate a couple more to the tank and they'll be too occupied chasing each other around. I dont surmise a convict in there is really a good view, they (convicts) will get very territorial but if they adjectives grow up together they should be ok.
Answers:    So many problems here. The convict should be kept alone in the 20 gallon tank. They are agressive fish and will eventually massacre the other fish.

The pleco needs to be moved well before he is 11 inches. Just hold on to in mind that he will need room to swim and I enjoy a hard time believing that he would have room much beyond 6 inches. The Pleco will also get agressive as he get older.

The barbs are usually nippers, but will do better contained by groups of 6 or more. If you can get the out of there, you could have up to 17 barb in that thank if that were adjectives that you had in there.

Sorry, but surrounded by short, you really need 2 more tanks if you are going to hang on to all these fish.-
just to permit you know, it is very normal that they nip at eachother. they are fighting fish, so they may also shoot eachother. i had some goldfish in with mine and they kill two of the goldfish and ate the tail off of the third. i don't know how many you could fit in that size container, definately more than three though. also they will eat "blood worms".
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