plants beauty

Hello folks

If you read my previuos post 3 weeks ago, i had i betta, 5 dwarf gouramies and 1 opaline and 1 pearl gouramies

i removed the opaline and the pearl

them my 4 remaining gouramies and fbetta, started to die a week ago

now i have a lonely dwarf gourami in the tank

i checked for excess ammonia, but levels are fine, there's no sign of disease(at least as far as i know) but i noticed this small amount of white foam on the corner of my tank plus there's a brown stain on the back wall of the aquarium

DOES ANY ONE KNOW WHAT IS GOING ON?!!!!

THANKS A LOT

Diana K

All the fish you list fight with each other to a greater or lesser extent. They are all territorial about surface area, and will fight to defend it. The males are particularly aggressive.
I had an Opaline Gourami (actually a color form of the 3-spot Gourami) that tried to claim all of a 6' long, 125 gallon tank.
I have heard of Dwarf Gouramis that are so aggressive to other species (not just Anabantoids) that he had to be kept in a separate tank.

Some ideas:

Death with no obvious sign of disease could be from the fish attacking each other.

These fish make bubble nests. The foam could well be the winner of the territory making his bubble nest.

The brown stain might be Diatoms, aka brown algae.

plants beauty

Thanks Diana

i removed the pearl and the opaline, and i all i had left is the dwarf fouramies and the betta, but they still they all died and i have one dwarf gourami left

what about this algae you mentioned, is it dangerous and why i have it?