Posted: Fri Aug 27, 2004 6:28 am
I have an APC Back-UPS ES725 on my main tank. It is rated at 725 VA (Volt-Amperes). It drives two powerhead-sponge filtes that draw about 10 Watts total. It has enough reserves to run about 6 hours in this set-up -- good enough for our summertime brown-outs. If I were to try to run my lights off it as well, I might get 20 minutes.