KnockOut Plus Ick & Fugus Treatment
All Natural Treatment and Preventative for Ick & Fungus.
CrystalClear KnockOut PLUS is an all natural, fish treatment that eliminates PLUS prevents external single-celled parasites or fungal infections. KnockOut PLUS works extremely well with pond fish species such as koi and goldfish and unlike most fish treatments, there is no need to remove your filters before treatment. Furthermore, when used routinely, KnockOut PLUS works as a strong preventative treatment. Use anytime new fish are added, during pond clean-outs, during spring start-up or any time fish are stressed.
KnockOut PLUS is a broad spectrum treatment for a variety of parasites including ichthyophthirius (Ick), sporozoan parasite, dinoflagellate infections as well as fungi such as saprolegnia, achlya, leptomitus and pythium. May be used with most invertebrates including snails.

You can use rainwater to fill your pond, but keep in mind that it is very soft water. If you primarily use rainwater, be sure to check your pH regularly because it could become too low and cause serous problems.