how many lights we talking about here?
most of your household timers are rated at 15amps, yes, even those that claim they are "heavy duty".
to get amps, you take your watts and divide by 120 ... this gives you a rough idea of how many amps you're dealing with.
most of the sw
people I've spoke with recommend leaving the fuge lights on 24x7 or having them reverse what your display tank is. for this, you need two timers.
I've got several different brands of timers, and although they all are working well, GE and Radio Shack are my favorites.
most of your timers out there of the analog flavor use little stops that you plug into the timer to set the ON and OFF times. That's fine for granny wanting to make her huge old house look lived in, but not for the demanding science that fish husbandry is
the GE heavy duty analog timer uses little switches instead of plug-in stops, and each switch accounts for 15 min time. It's also neat because if for some perverse reason you wanted to schedule a 30 min "storm" in the middle of the photoperiod, you can just flip two switches and the lights will go out and then back on
the Radio Shack heavy duty digital timer users a microprocessor to control the power, and runs off a pair of AAA batteries. I got this timer on clearance sale for $7 and it's the "cats meow" ... not only doesn't it mind getting unplugged, but it's percise down to 1 min intervals. your regular analog timers are good to plus/minus 5-10 min and get screwed up when you unplug them. only downside is the radioshack timer does not know about daylight time, so my tank is an hour off the others right now... I'll fix it sooner or later