Lastly, Will this dresser support a 30 gallon high?

if it doesnt sway when you and a friend sit on it go for it. also could diy it some to make it more supportive. big issuse is the height when you pull the doors out if it shifts the weight and causes it to tip
 
You could always add some supports inside the dresser for added strength. If you have seconds thoughts about whether or not it will hold, then don't trust it. It's a bad thing when all that water ends up on the floor, and then you will be out the tank anyway. Trust yourself.
 
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