Is this a good design to Build a rack system?

[PythonWallace]

Keep in mind that the more expensive plastic racks will last pretty much forever, but the melamine ones will be damaged if they come into contact with moisture.
They're expensive because the plastic they use is much more expensive than melamine.

I tore down a year-old melamine rack a few weeks ago and the surface above the tubs was yellowed, bumpy, and not even remotely waterproof.
Moving forward I'm only going to use it on my adult BP racks, which have enough gap between the tub and the shelf above that air moves freely to reduce or stop condensation.

My Melamine boards were from Menards. Others may be better.

That's true, and plastic is a lot lighter than melamine, too. For the price though, I like the melamine racks. On all future racks I'm going to use this stuff: http://www.kmart.com/shc/s/p_10151_1...1023x272xTier3 to seal the bottoms of all the shelves so they are completely waterproof. You can do 34 shelves for $40.