Nolvasan is effective in eliminating a wide range of bacteria and other micro-organisms when used as a cleaning agent, and I relied upon it throughout my zoo career.
Many aviculturists utilize Nolvasan as an additive to drinking water and hand-feeding formulas, most especially where the yeast Candida albicans is a concern. Its effectiveness in this role is, however questionable. The main problem is that the concentration that is safe for birds to drink (1 teaspoon per gallon per manufacturer’s instructions) may not be strong enough to kill all pathogens.
Frequent cleaning of your pet’s food and water bowl and bath, using hot water and Clorox, is a far better practice than is using water additives. Be sure to scrub all surfaces thoroughly – JW Pet Double Brush for Bird Waterers is superbly designed for this task. You can also wipe the interior of these areas (and the cage itself) with Bramtom Bird Cage Wipes.
I also suggest keeping 2 sets of food and water cups on hand. Air drying after cleaning, in sunlight if at all possible, is an extremely effective disease control measure. By alternating your food and water cups, you can assure that each will have plenty of time to dry out after cleaning.
Candida albicans is very common in most environments, and nearly always shows up opportunistically when any sort of avian health problem arises. You can learn more at: