rainbow sharks nipping at eachother.

[bianca_m35]

Hi guys im going to try and explain this the best i can. I have a 50 gallon tank. Has cardamine lyrata and ammania gracilis planted. Lots of hiding spaces. All the inter species get along fine. I had 3 mollies that previously lived together then my one female killed the other 2 mollies. Now i have an angel fish, 3 peppered corys, the one black molly, and 3 rainbow sharks. Every fish gets along except the sharks. They were fine, the biggest one picks on the other two but doesnt necessarily try to antagonize them. If they come near his bottom half of the tank he nips and chases them away but not any of the other fish. Every single one of the fish is in great shape including the sharks but he does chase them away and this never used to happen. For majority of the time they are on their own and dont bother but sometimes its a different story.

 

[AquaBarb]

As a general rule its recommended that you only have one Rainbow in a tank. They are very territorial and do not tolerate living with their own kind. In the wild they generally lead a solitary life.

3 in a 50 will give you big problems with aggression

 

[utahfish]

Yup one rainbow shark per tank.
Also mollies are hard water fish angels coreys rainbow sharks all soft water especially the angel.
Also angels are shoaling fish that need to be in groups of at least 5 in which a 50 gallon is way to small for a group of angels.
When you rehome two of the rainbow sharks see if you can rehome the angel then find your water GH and stock your tank accordingly, soft water fish or hard water fish not both. Good luck not surprised who ever sold you 3 rainbow sharks didnt tell you they dont get along

 

[Byron]

I agree with other members here. This explanation is from the profile I wrote on this species (Epalzeorhynchos frenatus) for another site a couple years back:

Compatibility/Temperament: Territorial and combative with its own species; best kept in solitude (as they seem to live in their habitat). Young fish tend to be secretive, but as they mature some can become aggressive, especially with their own or similar species. This "shark" will get along with some of the loaches (Botia sp.) but other bottom fish should be avoided. Upper fish such as the medium barbs, rasbora and danios would be suitable, especially in the suggested aquascape [see under Discussion]. In a large aquarium (6+ feet) a group of 6 could be attempted, but any fewer would likely result in the death of subordinate fish within the group.

The aggression has begun obviously, and while it may not seem like much, it is far more serious than it appears. Not only will the physical attacks increase, the fish are communicating chemically with phermones they release and read, and these alone can be severely stressful. We cannot see those, but we will see the eventual result...dead fish.

 

[Metalhead88]

Yup one rainbow shark per tank.
Also mollies are hard water fish angels coreys rainbow sharks all soft water especially the angel.
Also angels are shoaling fish that need to be in groups of at least 5 in which a 50 gallon is way to small for a group of angels.
When you rehome two of the rainbow sharks see if you can rehome the angel then find your water GH and stock your tank accordingly, soft water fish or hard water fish not both. Good luck not surprised who ever sold you 3 rainbow sharks didnt tell you they dont get along

Utah absolutely nailed it.

And 100x agree that whoever sold you 3 rainbow sharks set you up for failure.

As mentioned, you have a few issues here, some more obvious than others. The rainbow sharks will never get along and they aren't community fish either. They do better with similar sized cichlids and other larger fish. Cories will absolutely be picked on and mollies most likely. Angels can be susceptible to their aggression as well, but you may have luck since angels are big fish.