Miley,
He is going to have to get into a cycled and heated tank to help him. *I know you have been spending your money trying to get him what he needs but he is getting sick because he needs to be in a good tank with a cycled filter and heat. *It is going to be so hard for him to get better with no heat but you cannot heat a 1.5 gallon tank. *Is there any way you could at least get a large bucket (new one) and a heater? *Then you would still have to do the daily water changes but you could medicate him and keep him in the bucket or even one of those plastic Kritter Keepers. *Here are some that would be big enough to heat.
http://www.thatpetplace.com/pet/prod...itemKey=204236 http://www.petsmart.com/global/produ...N=2030170&Ne=2 http://www.petco.com/Shop/petco_Prod...riums-_-center
Then if you can get a 25watt heater at the petstore, he will be set. *Like I said if you cannot get the boxes above, a large brand new plastic bucket will do as long as you keep the water level down at least 2 inches from the top and white is the best color as it will make his world lighter and brighter.
He will eventually need a filter (sponge would be cheapest) but for the time being while you are giving him medication he does not need one. *
He needs some Jungle Labs Fungus Clear Tank Buddies or some Maracyn2 for treating him.
Rose