Hi CCL! Welcome to the wonderful and obsessive world of aquarium keeping! Are you using filtered water or tap with conditioner? Aquarium salt according to directions on box? Do you have live plants? With yr phosphates and nitrites elevated you may be overfeeding a bit. A fishes stomach is only the size of their eyeball. One tiny pellet for a Betta will be adequate and will help reduce the algae bloom as well. I also fast my fish every Sunday and they are healthy and beautifully colored. Their immune system comes from the gut and overfeeding harms their entire immune system. It looks like you are almost through your new tank cycle. Keep doing your water changes daily until Nitrites consistently are at zero. His fins looked frayed and not really fungused to me. This is probably from ammonia/nitrites or the filter flow is too strong, or too rough with water changes possibly? Read, read, read on Bettas and newbie basics. Amazon has very affordable UV sterilizers inside filters (9watt) that really help with algae control (about $30). Just make sure your flow is really low in his tank. They live in puddles and still water in nature and cannot handle rapid flow. Kudos for testing your water...keep at it and keep us updated!
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