So after much deliberation, taking into account all the great advice and weighing the amount of work involved in creating a proper solution, I tested out a few solutions. First off, I cut new holes in 1 tub about 2" lower. This created an ideal water level but the new drains were lower than my 4" drain pipe, which meant I would have to raise all my tubs about 4" in a room where height will be a concern. Also I wasn't in the mood to cut/file 21 new holes and create new bases. So next I tried the Lost method (TM) lol, I cut a 5 gallon bucket collar, placed into upon the lid (the hole is too small to slide the bucket in yet!) and slid the 10" net pot in. This raised the entire net pot out of the water, which is not ideal, but is definitely on the right track.
The temporary but somewhat invasive solution I came up with was to raise the rockwool cube as high in the net pot as possible. With these plants being 3 weeks into veg they had produced a decent amount of roots. To make this process as gentle as possible, I submerged the root zone in a 5 gallon bucket and began pulling up the plant while shaking it, allowing the hydroton to resettle underneath the rockwool cube. This put the maximum amount of space between my cube and the water level. Today I'm on the hunt to find an improvised alternative collar.
My advice to anyone setting up their mpb, cut only 1 bucket first and test the water level before cutting the rest of your tubs. Or just use the lost method (patent pending)
