NQR Gold Gourami

Question
First the specs on my tank: 29g freshwater - established 2.5-3 yrs ago. All fish are full grown unless listed - 1 chinese algae eater, 1 gold gourami (male), 1 blue gourami (male)(I was told he was a dwarf when I got him but he isnt colored like the dwarfs Ive seen online), 5 serpae tetras, 2 hatchets, 3 cory catfish (new within the last month and not mature). Problem: I returned yesterday from a week long vacation. I noticed my tank was cloudy and had lots of algae. Also I noticed my gold gourami was just hanging at the top corner of the tank, kind of slow moving, and then saw his right pec fin was ripped in half (just the thin, moving part, not the part that actually attaches to the body). When I fed dinner, he was not interested in eating. I also think he looks a little thinner than when I left, esp compared to the blue gourami which is normally smaller than the gold.

I found that the filter had stopped working (step dad was watching the fish and Im thinking he over fed them which caused the nitrates to spike and cause the algae to grow which then clogged my filter). I tested the water and nitrites and ammonia were 0 ppm, pH was 7.8, temp 78 degrees F, but nitrates were 80 ppm. So I immediately did a 40-50% water change, cleaned the filter, tubing, etc. Let that sit over night. Checked the nitrates again this morning and they were around 40ppm. So I did another 30% water change and also double checked my tap water to make sure it had no nitrates in it (it doesnt). Tried to get the gold gourami to eat this AM (flakes and blood worms) and again not interested at all.

All of the other fish are normal. Im assuming the gold hurt his fin with another fish, likely the blue gourami. I know that chinese algae eaters can be aggressive but mine hides in the pirate ship all of the time and when he comes out, goes to a corner or on the glass and then back into the ship. The only conflicts Ive seen (day and night with lights on and off to see how they interacted) was between the two gouramis. However, the gold is the dominate one (and almost 1/3 bigger than the blue) and only chased the blue one while it was feeding time. There have never been any injuries or bites or anything. Until now with the fin on the gold.

The gold is just hanging around at the top of the tank, not moving too much. Now when he wants to, he can swim fine, isnt listing off to the side, etc. No growths or anything either. He still goes up and gets air like normal as well. But he used to cruise the top of the tank and was pretty active and now hes not. The blue gourami usually will hang out mid tank and sometimes goes to the bottom by some plants to rest. Last night while feeding, if the blue came near the gold one, the gold would back off which is not normal. This morning I noticed the blue hanging out near the gold and neither of them were chasing each other or anything.

I was worried that the blue was bothering the gold one and thats why he wasnt eating. So due to it being Christmas and no stores open, I poked a bunch of holes in a tupperware container and its floating at the top of the tank with the gold gourami in it. I tried putting a few flakes and blood worms in there with him and again, not interested.

His right fin is def split but other than that, is moving and is not hindering his swimming.

Im just not sure what to do. I really dont want to lose my fish. Ive had them all for over 2 yrs (except the corys) and am a little attached. But the gold gourami just will not eat and personally I think he looks thinner esp between the mid section and the tail as its not as full looking. I did add some Stress Coat to the water last night just in case he needed it for the injury.

What do I need to do for my gourami? Obviously I cant make him eat. Im doing everything I can to get the nitrates back in order now that I have the filter up and going again. My water parameters have never had an issue since I first cycled the tank. I use tap water but am on a well and there are no chemicals added (my water tests perfect for my fish even the hardness). Any other suggestions? :(

Answer
Shantel,

Since it sounds more like any injury than any disease, I would not add any medication to the tank. Remove the injured fish and put him in your quarantine tank that also has been cycled. Some people will say to add aquarium salt to the water, but I always recommend salt water baths. They are more concentrated, and work great with my Betta's. If you add salt to the water, the ratio is 1 teaspoon per 1 gallon of water. However, the salt water takes the place of the water taken out of the tank during a water change. So, you take a gallon of water and dissolve 1 teaspoon aquarium salt. If you only remove 2 cups of water, you will only add two cups of the water with the salt. Once he has healed, you can put him back into the main tank and then start removing the salt water from your quarantine/hospital tank.