RODI Storage Container issue - Mold

[ReefinRick]

I have a 6 stage RODI unit which feeds a 32 gallon Burte can with a float valve installed. I have an ATO pump inside the can and an MJ1200 Pump. I use the MJ1200 to transfer Filtered water from the holding container to the mixing container for a water change. The ATO pulls filtered water when it is needed for top-off. I have a lid in place with a few notches for the cords and hoses. This sits in my basement behind the wall of the Aquarium location next to the sump. This is a spare/junk room.

Today I pulled the lid off to get to the ATO pump and the smell smacked me in the face. I noticed mold and mildew on the underside of the lid and top end of the container above the water full line. I need to know what can be done to prevent this. I cleaned the container and don't need info on that. Just what, if anything, am I doing wrong that this cest pool was living in my basement?

Thanks in advance.

 

[odstar]

Try looking for some blue food grade barrels. You can usually find them on offer up or Craigslist.