Preventing a flood

[USMA36]

I am in the process of setting up my first aquarium. I have 2 tank options. Both used both 150.00. Option 1 is an undrilled formerly freshwater tank. I'd buy an overflow kit with emergency drain from glass holes. Option 2 a used tank from lfs with corner overflow but now emergency drain. I am paranoid of a flood caused by a blocked drain. I have been looking for a return pump shutoff but I haven't come across anything other than a float switch which I am told aren't all that reliable. What are your opinions? Any ideas of fool proof flood protection?

 

[Cary Meredith]

I have a 125 reef ready, with 2 overflows over 10 years, no flood or plugged holes, and I have a 40 breeder in the same system, only one over flow, no plugged holes or anything since that has been in as well, have you heard of overflows, are they standard overflows or custom built?

 

[erinmegan85]

I've heard of more issues with hang on back overflows flooding than drilled tanks with built in overflows. If I had to choose between the two I would go with the one with the corner overflow. That's just me though. Unless the kits from glass holes require you to drill the tank, in which case be sure whatever tank you're looking to put it in can be drilled.