Sorry, we don't mean to pick on you
Wow, that's a 30g ?
Looks like a 20 tall in the pic
My system is only a 75g and I currently have a 20g QT that I've been using for new fish, but I plan on a larger one soon, before my critters grow. Probably gonna need a 4' 50g or so
I'm only thinking about what you would be faced with if something happened to your DT, and you had to put all your fish in a QT at once ?
I'd think you'd need at least a long 50g to house all your dudes. The bigger the better - 75-100g
If you don't mind an idea, and to keep access to your return pump ...
Have you thought about building a pony stand for a bigger QT ?
Just something with, say, 1 to 2 foot feet or such, right on top of your bench
If I judge your space correctly by your pics, it looks like you have room for at least a 3 footer, if it was high enough to access your return pump