I'm waiting for the other shoe to drop... this looks too good.
Hate to simplify things for you, but how about a $20 lawn tractor battery(wallyworld) and make a trickle charger from a wall wart psu?
Or you could just use a http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=3418. straight.
Unless you've got enough in your junk box like me...
I went to radio shack and bought a 12.6 volt dc transformer and solder that to a rectifier rated for 400volt 6 amp, then hooked a wall plug onto it and shoved everything in an enclosure box! for everything it cost me $18. The pump works now!! the only thing I have left to do is possibly install some float switches in the fish tank or the new fill tank and work on finding a timer that is synchronized to one clock but can individually control 2 seperate outlets down to the second!
I found one and it is made by chrontrol... They sell them for $300 something dollars. I talked to one of the engineers and told him what I was working on. He found it very interesting and understood I was poor college student he said he would sell me a chrontol timer for $99!! I still dont think I am going to buy it, I would rather build it myself with some of my friends.
One thing I have thought of though is if you have a sump you can actually take old water out of the tank and add new water into the tank simotaneously!! I am going to test it out on my system soon! I just hope my sump or tank does not over flow.
)
