Hi thank you for looking and helping me with this issue. tank is 3 gal. used to house neon tetras then baby guppies and was empty for a long long while, well yesterday I went out with my son to a pet store and finally I decided it was time for him to have a fish again so he chooses this cute male betta fish, right from the get go I noticed some fin rot, but I said treatable right? he was set on that one so we brought him home, I cleaned the tank with hot water ONLY, used my regular sponges (I do have a 20 gal long running and used to have a 5 and 10 gal. have had a betta before for 4 years in a 5 gal, then I moved him to my 20 and put his home away, also a 3 year old ranchu goldfish, and now the guppies) acclimated the fish before putting it in the tank (after cleaning I set it up and let it run for a while) I put the fish in and I noticed from there that he is bottom sitting, has an S or sometimes U shape in his body, as well as bended sometimes when he tries to spring up to swim, and take a breath, he is better now, not as crocked anymore, but still I can see it, so I fed him, he eat well yesterday, today I gave him antibiotic food, so far he has not eaten it, and I proceed to take the water parameter and they are like this: ph 7.0+ it is a darker blue but not very dark if you get what I mean. High ph: 8.0 now I have never had such high ph but we just moved to this house and I really didn't tested the water when moving, yes I lost guppies babies but all my adult stock is still alive, and I don't even know if this higher ph will be beneficial for the betta. ammonia:<0 as clear as water can be, I have never seen such a thing, yes I know the tank is set up new but I used 1 gal. of water from my 20 gal. tank and I put media that I had in my 20 gal. tank cuz I knew I was using that tank again and so I just kept the media in the 20 gal. tank mean while I decided what to do with it... Nitrite:0 no concerns here Nitrate: 5.0 thinking of doing a water change just because of the nitrates, but then I don't really want to stress even more the fish. should I be thinking about medication? a salt bath? adding aquarium salt to the water? should I be concerned about the high ph?