I have two Rubbermaid Brute 32 gallon containers I got from Lowes. I have been fighting brown algae outbreaks the next day after weekly 25% water change. I replaced all my rodi filters and resin. Coming out of RODI unit the water test is 000. After circulating and heating water for just a few hours I get a reading of 065-075. I thought my containers were food safe and work great with the caster base to roll from laundry room to tank.Are the Brute containers that Lowes has food grade?