I'm not saying in any means they don't save lives or serve purpose, but for use totally around the fish tank can and will be a problem......Most people have their lines or circuits overloaded as it is and most don't know how to break down the loads on their circuits as well which creates another problem in itself....
The article I'm referring to is in March issue of FAMA titled "Life Support", page 34 under Ground Fault Interrupters.......The aurthor of this article is Dan Theisen......He states he knows they are a livesaver, but a GFI has the potential to rob your tank of life. If a GFI trips unexpectedly and goes unnoticed then your power hungry reef tank is dead in the water.
Multiple circuits will help, specially, if one of them is a non-GFI circuit. In the cabinet next to my tank (but away from moisture) there is a single powerstrip that is hooked up to a non-GFI circuit. There is a pwerhead and (in the winter) a heater plugged into this strip. This way I know my tank will have a critical supply of oxygen and heat even if the main GFI circuit trips. The powerstrip has its own kill switch so it is a simple matter to cut power each time I need to put my hands in the tank. Just don't forget!!!!!
Avoid the plug-in type GFI's. They are very ficle and prone to kicking off without provocation. The one I tried would kick off occasionally from the start-up of the metal halide ballasts. The hardwired GFI receptacles are much more reliable. Call an electrician if you don't feel comfortable wiring one.
Again he's not saying they are bad and not a lifesaver, but they have their places and uses.....Again my point was they are potential problems if the inital circuit is overloaded which most people do run into that problem.....Most people have 15 amp breakers and put a GFI outlet and plug everything into 1 power stip in that outlet and they forget about all the other stuff on the same circuit, or maybe it's fine, but someone adds a heavy draw item like a blow dryer or curling iron to that circuit for a short period and it's very possible to trip the GFI.
I had a similar problem in my bathrooms....I had my house built 5 years ago and my GFI's would trip if both my wife and daughters would run blow driers and curling irons together.....I'm lucky due to my brother-in-law being an electrician owning his own business and I work on the side for him as well, so I called him in and the builder did use 12/2, but 15 amp circuit......Again some people aren't sure or don't know, but will put a 20 amp breaker on 14/2 wire, which is a heavy load for that wire. Since the breaker could be swapped out due to the heavier gauge wire it wasn't a problem. I've installed GFI's and have found them bad right out of the box after installation.......
Again they are lifesavers, but caution and common sense has to be used with all items and electrical common sense and some knowledge as well.....Know what your load capacities are per circuit and what each item is drawing......In designing my new circuits for my fishroom, I thought out about what was going to be where and such, and ran my lines and knew ahead of time what type of equipment I was going to be running and split my loads up evenly among the 4 circuits that supply the fishroom, knowing I have an overkill, but will never exceed the 80% load your suppose to or safely put on a circuit.....