Overflow Box Questions(again)

So I've been doing lots of research on overflow boxes and I still can't decide whats best for me.
I've been trying to decide what to do about my 75g I was just given. Some people say don't risk drilling it and just use a hob overflow box, other people say stop being cheap and go buy a tank that is already drilled.
Here's my problem...
The only reason my wife is letting me set up this 75 (or "unneccessay expense" lol as she likes to call it) is because I got it for free. If I told her I was going to buy a new tank I would probably get shot since there is already one sitting in the garage. So buying a new on is kind of out of the question.
Which leaves me with getting a hob overflow box. I'm leaning towards eshopps.
Even though some people swear by them, I'm still worried about ending up with a flooded floor. Honestly, who here has had this problem? The way I see it, if you have a power outage(which happens quite a bit here in S. Florida), when the power comes back on and the return pump kicks back on but if the overflow box loses siphon it ends up overflowing the dt.
When the power goes out does the u-tube hold water and continue draining when the return pump raises the dt water level again?
With a QuiteOne 2200 return pump that I'm using now on my 20g, what model overflow box should I go with?
Also does it make sense to use 2 smaller overflow boxes ( for additional insurance) as opposed to using one large one? Maybe have one feed the sump, the other feed the fuge.
Thanks,

 

i have used overflow boxes for a year now and 10 years ago i used them for 5 years and never had a problem...

 

When the power goes out, the water stops flowing, but the siphon holds and when the power goes back on it just slowly starts draining again. If you monitor the overflow for air bubbles, you should be fine. If you get two smaller overflows, each needs to be able to handle the pump you have as if it is too small, the pump will run dry if one of them stops.

 

Drill the tank & get an overflow from Glass-Holes.com dope aquarium stuff. Internal are much better than external. You don't have to worry about air getting into the U tube.

 

Make sense, thanks GuitarMan
I hear most problems are caused by air bubbles collecting in the u-tube. Is this pretty common, or is there any way of preventing them from getting in there?
Instaed of getting two overflow boxes, would you reccomend one very large one(I believe the eshopps 1200 and up have two u-tubes and two outlets)? I guess I could run one outlet to the sump, the other to the fuge?

 

I agree but I've been told the tank cannot be drilled.

 

Who told you that and their infomation was based on what ?

 

The bottom probably can't be drilled but most sides can be. The only one that uses tempered glass throughout is the 55 gallon Marineland tank if memory serves me correctly.

 

Don't risk drilling it. Overflows are very simple to use and with just a shred of common sense easy to keep running well. I use an Eshopps overflow that I shut off every day for feeding. It has never once lost siphon after the 100's of times I've shut off flow.

 

internal overflows are waaaaay more sexy than external overflows... ;D ;D ;D