Purple-spotted Gudgeon is the common name, he is in fw with some catfish and a butterfly fish. i never see the catfish bother him. i've had him for about three months. i put fw aquarium salt in about every other water change and change the water 1 to 2 times a week. he was very aggressive up to 2 weeks ago but then just started sitting there. sometimes he will sit at the surface but just under the water level. i dont think the marine salt would settle w/ the cats but im not for sure. thanks for the help.
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29 gal. fw
1 african butterfly
1 Purple-spotted Gudgeon
2 bichir: p. palmas & senegaul
6 catfish: indian sun, african silver, bristlenose plec, snyo. euruptis, striped mystus, and tiger shovelnose