This calculator is meant to assist with treatment of fish eggs to prevent fungal growth. Methylene blue may be used throughout the course of fry development, but we generally recommend only using it until initial hatching. Iodine treatments should be done for 30 minutes a day, and peroxide treatments for 15 minutes a day.
The peroxide treatment suggestion is based on a water temperature of 82 F (27.7 C). Lower temperatures may require higher doses, such that 75 F (23.8 C) would require twice the dose, and 65 F (18.3 C) might require 4 times the dose.
These are suggested guidelines based on several studies done on freshwater Angelfish, Danio, and Channel catfish, and may or may not apply to your particular species.
Some studies suggest that continuous use peroxide treatments may be used at on tenth the dose suggested here (as opposed to 15 minute treatments at the listed dose). Continuous use treatment with iodine is strongly discouraged.
Doses given are based on standard strengths of 2.3% for methylene blue (Kordon), 10% for Povidone-iodine (Ovadine Betadine, most generics) and 3% hydrogen peroxide.