Hi Everyone, FishLore forums have been awesome helping me to set up my new Betta tank. I have a 5Gallon tank with a single male Crowntail Betta and two Nerite Zebra Snails. The tank was cycled and I have been testing the water everyday with good results 0 ammonia, 0 Nitrite & around 20ppm Nitrate. I also used Pure Aquarium to help the good bacteria along and seems to be working great. I finally got my Betta two days ago and things have been going well. He was pretty active and after a little persuasion he ate some blood worms (around 3-4 two times yesterday) as he wouldn't touch the flakes I got and cant get hold of any pellets yet! He ate those fine but today he's like a different fish. I noticed this morning that he seems to have a cotton like growth on his one Gill, he is also very lethargic and slow. I turned the filter off because he seemed to keep drifting into it and the spray bar dragged him down. I had intended to change the water today/tomorrow by 25% for the first time anyway and have now done so (around 30-40%, all new water treated and added when was same temp as tank). I did a lot of research this morning and from what I have read and researched it looks like he might have a fungal infection so to act quickly I have added Interpet Anti Fungus & Finrot exactly as it said to on the label during the new water change. He won't eat at all and is just laying within the leaves of the Java moss I have in there. Any advice would be really appreciated! My main questions at the moment are: 1. Is turning the filter off the right thing to do if there is new water/medication? 2. I'm still not 100% sure that it is a fungal infection, could it be bloating? He doesn't look too bloated to me... 3. I added some Tetra Safe Start to the new water as I read that the medication could kill some of the good bacteria so read that was the thing to do. Is that correct? 4. I thought that maybe stress isn't helping so for the moment I've covered the tank. Would that help? I know there is Stress coat but haven't been able to get hold of any at the moment. Ideally I wanted to get hold of Tetra Lifeguard as it covers most common sicknesses but there wasn't any in my local store and its very expensive so settled for the Fungal medicine instead. One thing I did notice is that my tank had a dying plant in it (The one my Betta liked to sleep in) reading up on it I think it isn't a true aquatic plant so I was mis-sold in store. It did have some white Algae growing on it which is what initially I thought the cotton like substance was on my betta Gill originally. I have now removed the plant and did the water changes after I did so. Could the plant dying of caused the sickness? It seems very fast considering its only been two days? Sorry I know its a lot to read! Any and all help would be really appreciated! Thanks.