Our two-year old betta fish Dana has become increasingly lethargic over the last month. At first, he noticed a small bump on his left chin that resembled a fish pellet under his skin, however it seems to have completed disappeared and our local pet store had no idea what it was (they confirmed it wasn't a bloated stomach or anything parasitic they could tell, etc). In precaution, we immediately changed his tank while keeping 25% of the original water aside and adding Essentials BioBoost Biological Water Conditioner and Splendid Betta Complete Water Conditioner to the water, however we are very new to fish care and want to get some expert opinion on what we should do. We have been adamant about scooping uneaten food out of the water, but he is eating a lot less than he use to so we've reduced feeding to once a day (two-three pellets of Elive Betta Bites). Upon a recommendation from an online source, we purchased Essentials Betta Salt and administered .5 tbs to his 2.5G heated (79º) tank yesterday with hopes he would perk up. We also have been testing the water with Tetra 5-in-1 EasyStrips calculating the most recent results below: Nitrate [NO3]: 20 mg/L -Freshwater Nitrate [NO2]: 0 MG/l - Freshwater Total Hardness (GH): 150 - Freshwater Total Alkalinity (KH): 40 - Freshwater pH: 7.6 We're not sure how to fix the problem or what's wrong with our fish, but we're looking for any specific suggestions you can give to us. We're also looking into purchasing a larger tank and live plants to hopefully help him be more comfortable. It is a learning curve for us to learn how to properly care for him, but we are up for the challenge as he is an important part of our household. Any advice is greatly appreciated.