We just noticed a fair amount of white slime in our freshwater tank used for adding water to the system to replace evaporation.
The system is coming off-line for clean-up and re-evaluation.
A 50 foot RODI tube will be run to the sump every few days too add some freshwater (on a timer) until we can make a decision on the best sub-system going forward.
This is easier than carrying a few gallons of water from the kitchen to the aquarium.
Can top-off water go bad? Can deleterious bacteria grow in the freshwater top-off reservoir and contaminate the entire system?