What did you do today?

[Taffy]

The fertilizer tanks I use are different than the totes you are using.  These are large tanks that are piped to irrigation systems to deliver fertilizer at a set rate.  The top of the tank has a large screw on lid where it is filled with the liquid fertilizer.  I use 2x4's and screw them to the lid hole to raise above the sides of the lid lip then screw a leftover piece of the tank Ive cut out to cover the hole.  This covers the hole but also allows ventilation so there's no condensation in the tank.  They aren't fancy but they work great and last quite awhile.