Freshwater Aquarium/Blue Gourami


I have a blue gourami and it changed colors over night. Now the front half is the normal color and the back half is black. I'm not sure if its from stress or what. Anything you can tell me will be much appreciated. Thank you in advance.

Hi Travis

It is normal for most tropical fish to change colors with their mood. Usually, when stressed or under certain light, their colors will fade. When content, in darker surroundings, or a perfect light, they will show intense color. This is one of the first signs to most aquarists that there is a problem in the tank or when all is right with the tank.  There is also a noticeable change in color as juveniles mature, especially males. Make sure your water is clean, but it sounds like he is just fine.

Hope this helps you, good luck!


Freshwater Aquarium

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Richard Hight


I own and maintain several freshwater aquariums from 2 to 180 gallon. I can answer most questions about freshwater aquariums, including setup, cycling, maintenance, compatible tank mates, feeding. Moving? I've moved fish both across town and across the country and can help you get your little aquatic friends to their new home safely. I know and have experience with most freshwater community fish, South American Cichlids and African Cichlids. I don't answer questions about Goldfish or keeping Goldfish with Tropical Fish. I also don't answer questions about keeping crustaceans (shrimp, snails, crabs etc) with Tropical Fish, nor questions about saltwater fish or aquariums. I'm not available to answer questions on weekends, this is when I do maintenance on my own tanks.


Many years of personal experience with community tank fish, semi-aggressive fish (Barbs, Tetras, etc), Angels, South American Cichlids and African Cichlids.

HSG 2010-2011 prof

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