Update 8/9/17 4:30pm: Last night Rex started staying at the bottom of tank. I had put in another filter on Monday, added nitrate absorbing media and performed water changes getting my nitrites down to 0ppm, ammonia was 0ppm and nitrates to 10ppm. Today he wasn't moving and I tested the water again and somehow within 24 hours my nitrates significantly increased. I took Rex out and put him in a clean bowl to see if he was still alive but I am devastated to say that he has passed away. I am so upset & now that he is in the bowl and I can see him up close I found grayish purple/red marks on him which I mentioned I noticed faintly before. Does anyone know what this disease causes these lesions? I have included new pictures below. Original Post: Please Help Save Captain Rex! He hasn't been acting himself the past couple weeks. I've tried treating him with aquarium salt and anti fungal treatment because it has worked in the past for a minor fungal infection. Unfortunately when I first got him in December he had been mistreated prior to my saving him (he was living in a child's room in a .5 gallon carrier tank, 67 degree water and he had major fin rot). I rescued him from the family and bought him a 2.5 gallon tank, heater, filter, live plants, top of the line food, treats, etc. I've had him for about 9 months now and he has flourished. I moved in April and during the transport & despite my efforts his tank got down to 70 degree range & prob caused some stress. He was doing well April-June but the past few weeks he hasn't been as active and lately he hides in the corner of the tank at the top behind the filter or on top of the heater (which he has always done to rest his fins). The heater has been unplugged bc it has been way too hot and even with A/C on his tank will not drop below 80.5. On average his tank is kept around 81-82 degrees (often getting to 83 due to hot weather without the heater plugged in). His behavior is very strange he acts like he is skittsh now if I turn on the light or go near the tank he goes to the other corner and hides. A few times he tried to eat blood worms and would act normal but then miss and start darting around the tank ultimately going back to the corner. The few times he has ventured away from the corner I saw him once on the gravel hiding under an almond leaf and the other couple times he has left the corner he darted at lightning speed across the tank and was banging into the glass frantically. At first I thought it was old age or the water was too warm but the water temp has never been an issue before. his coloring has also dulled back to the muted green and when I shine the light on him I see an extreme golden sheen (which I was told was his iridescentce before). I know when the flash is on the camera (like it the pic below) it makes it appear to be velvet but I am unsure that is the case. I tried covering his tank with towel and turning up temp between 82-84 for 5-7 days and added aquarium salts as researched. I also notice some areas that look slightly cut up (you can see in the pictures) almost like scales are missing but I do not see red or grey coloring in the wounds. There is one teeny white-ish dot on his head but I don't think it is ick. don't know what to do, I bought tons of different tests, medicine, etc. I read the best way to treat velvet is wutg Fritz Coppersafe and I dosed accordingly and nothing seemed to change. His water parameters have always been fine - though this week the nitrates were in the "stress" range at 20ppm and my nitrites are 1ppm (probably from unrated food I haven been able to remove). The tap water (I obviously condition) at our new house has a really high PH (~8.3) and the well water at our old house was still high but not as alkaline. With the PH being high and Extremely hard water I don't if that could be contributing). I tried adding a tiny bit of distilled water to lower ph but it doesn't have minerals so it isn't a good option. I don't know if I should treat him with Seachem Kanaplex (I purchased a few days ago). I also bought betta revive and I have bettafix. Please Help!! I have included pics of when I first rescued him and a few months later (before and after) and some pics of his rapid decline in July. He won't eat and he hides in the corner please help! Poor Captain Rex is on borrowed time.