Seltzer Water Freezing Point Aquatic Tiny Worm-like Parasite?

Aquatic tiny worm-like parasite? - seltzer water freezing point

I have (a brackish some sweet, looked a little salt water) aquarium with 8 freshwater puffer fish in it and 1 piece of fish in Africa. They are fed frozen mosquito larvae and snails only small aquarium. I live in Southwest Florida and tap water there is fish. PetSmart time and I will take her a couple snails invading my aquarium fish food and have seen recently, very little hair, like a parasitic worm that nothing outside of rocks in the aquarium from time to time in a twisting motion. An employee said that she "worms known," and believe that they have a belly tank Fire Toad, but they do not know what they are. I'm having trouble disposing of them, but it seems that the direct impactmy fish. I know you are probably not anchored, they only value to the fish. Sometimes I can see, curling into a ball, and when they do, it is difficult to follow, because it looked like the end of bubbles in the water. If anyone has any idea what they are and how to get rid of, please let me know what I'm doing and what money can buy. I just tried this in the future, Alka-Seltzer tablets you drop into the aquarium (not) remember the name that will be free of parasites from the aquarium, and if it does not work, I have tried everything straight, the aquarium clean and everything associated with burning hot water, including the replacement of filter elements and all. I do not want usomewhat dangerous for my puffer fish. Please help!