Total hardness is GH and carbonate is KH2. Don’t have a test kit for gH and kH but here’s the pH, total hardness and carbonate levels: pH-7.0, total hardness-100ppm, carbonate-120ppm
Here’s what I hope is a better photo.Honestly need a better picture of the fish from profile view. The blister on his fins is not the thing to worry about.
Do you suggest stop feeding them for a period of time and do a large water change?For got to say -
Nitrate is not OK. it needs to be kept below 20 ppm. The UK allows up to 50 ppm in tap water; in places where it is this high, it's difficult to keep the tank level below 20 ppm. But if your tap water is below 50 ppm, nitrate is being made in the tank and it needs to be lowered. The usual way is by not overfeeding the fish, and by large weekly water changes.
I have never seen a red female dwarf gourami, they are usually silver with this colour morph.