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My cichlid tank has algae, bugs, and sick fish. What's wrong?

Updated On September 23rd, 2025

Pet's info: Fish | Unknown - Fish

I have a few problems in my cichlids tank currently. 1. There are these tiny white gnat like flying bugs coming out of the water? 2. Brown algae on the glass won’t go away! But I have snails and an eel so I don’t know what to use that won’t kill them 3. my tiger Oscar likes to lay at the bottom? All the fish seem to be breathing heavy but ph and ammonia are normal 4. Live plants have some sort of dark brown slime on their leaves won’t go away 5.dempsey ‘shivers’ or twitches recently

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1 Answer

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Answered By Angel Alvarado, LVT

Licensed Veterinary Technician

Published on May 20th, 2018

Those could be copepods. They are typically harmless and difficult to completely eradicate. On the good side, they are a sign of a healthy tank and are useful in eating decaying matter in the aquarium. The brown algae can be due to insufficient lighting or lighting periods. You can wipe down the glass and plants, perform a partial water change and increase lighting. It can take weeks to month to resolve. Use only aged or conditioned water that is temperature matched to prevent stress or shock. Confirm stable water chemistry and quality. Make sure the water temperature is correct as well. Too warm or too cold can cause stress. Look the Jack Dempsey over for signs of injury or infection. Ich, bacterial infection or fungal infection can cause the fish too twitch or shiver. Plain aquarium salt (NOT table salt or Epsom salt) dissolved at 1 tablespoon per 5 gallons of water is a great general tonic that can reduce stress, improve gill function, treat minor infection and aid in any recovery. The eels should be fine, but the snails should be moved temporarily. You can relocate both to a separate tank to be completely safe. Treat the tank for 10-14 days then reassess the condition of the fish. Perform a partial water change afterwards to reduce salinity before you returns the eels and snails to the tank.

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