Hi-
I also use RO/DI water. Yes when you use RO/DI water it strips the water of 99.9% (in my unit) of impurities and bacteria. My water has a ph value of 5.0-6.5 out of my RO/DI system (more natural), out of the tap the water comes out at 7.5-8.5. My tap water is very hard and has a bunch of junk in it, tap water will differ from sate to state. When I use tap water my chameleons have allot of excess salt secretions from there nose, with RO/DI not much. Another advantage is with auto misting systems you don't have to worry about clogs from the water. When you mist 3 times daily with my tap water a white hard water film will accumulate on the leafs which doesn't look good. If you are using RO water it is the same as much of the bottled water. If you think about it chameleons would be drinking the rainfall drops not water from streams/rivers/lakes that have water with more minerals. If you are concerned about minerals your vitamin dust should take care of it.
I do use tap water as well for my outdoor misting system, and have had no problems other then the white film the water leaves behind. With the indoor cages I try to keep the way the cages look better then the outdoor cages I.E. the hard water stains. In the colder winter months the chameleons are indoors 24/7 in the hotter summer months they are outdoors 24/7. To setup a system that I have indoors outdoors is not hard just expensive and takes up allot of space. The outdoor cages are misted 4 times daily for 30 min each mist. To do this I would need a large reservoir that dose not leach toxins from the plastic (food safe) and a large pump to handle the 30 min misting. After looking long term the system I have in place now will be just fine.
So I think it comes down to a personal preference when choosing the water type and where you live. Bottled water is filtered water, in some cases it is just filtered tap water. What ever minerals that are filtered out I am sure are replaced with your supplement dust and gutload. I would think that all the harmful stuff filtered out of the water would out weigh what little good things are in the water. Hope this helps!
P.S.- Avoid ice cubes and cold water altogether.
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John W. Lucas
CHAMELEON PARADISE
Feeding Baby Chameleons
Caging Baby Chameleons
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