I believe my betta Max has internal parasites. He's thin, and I spotted white stringy feces once. About the feces: I treated him for fin rot recently with Tetra Medica General Tonic. After a while, I noticed that the medication caused the live plants in my aquarium to die. I cleaned the aquarium and got the plants out, but some remained in becuase I didn't notice them. I was away for two days, and my family took care of Max in the meantime. When I came back I noticed the plants that were still in released some sort of white stringy things. - so I'm not 100% sure about the stringy white feces. He's eating a lot, but he's thin and the stringy thing made me worried. I won't be able to get any meds soon, what can I do on my own to help him? He's in a 4.5 gallon heated with a 25W heater on 28 Celsius.