No as you don't know what else comes from the air ?
Many suspect the metal in the dehumidifier is not proper for fish water ?
I run a dehumidifier basically 24/7 and have never used the water although others have asked this question ..
I never heard anyone say they thought it would be ok ?
Get an RO unit ..
First you should get a TDS meter [$20] and find out if you even need RO..
I seem the only who holds any validity to the use and reading them..
This would worry me if I wasn't the only one who can breed rams !
You would like your TDS to be under 200..You still need to know your other parameters as a baseline but they will be useless when it comes to adjusting your water ..My parameters barely shift when I mix my ro and tap but I lose 200TDS …