Which shelving unit will work best

I think any of them are fine.

I bought this on sale from Menards for $39, the shelves are rated 350# each. (evenly distributed)

I have had this set up for over a year.
Now there are 3, 20 gal tanks on it.
Before that I had a 37 gal on the middle shelf, and a 20 above it.
I have had a 37, a 10 ,and a 20 on this shelf...

And havent had any concerns.

It is rated 350# Per shelf.
And it seems to handle it just fine.

IMG_2938.jpg
 
Yep, have a wire rack one here with the 350 lb per shelf rating...no problems. If the wire bothers you, just place a 3/8" sheet of plywood under each tank. Leave your self adequate room on the shelf spacing to get things in and out of the tank and to do maintenance.
 
from your first post i would pick 1-3 but not 4 simply because #4 has a much lower weight/shelf rating.

wet particle board=cardboard so avoid the particle board shelves.

i have a wire rack like that but it is a little wobbly (because of an uneven floor and carpet) and i want to secure it to my wall before placing a 10gal tank on top of it. a 10 gal tank will be the only tank on it so it is going to be extremely top heavy...hence the securing to a wall.
 
ok thanks. now i just need to find a cheap 20 gallon long so i can divide it into 3 compartments for different shrimp.
 
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