This sounds like it would alleviate most of the issues. I was thinking if it was just one line from a GFCI outlet at the house and plugging in all the system on it, that anything tripping would leave the whole system down.
I think separating the timer and the other to separate circuits is a good idea.
I am also needing air pumps and air stones. I have a 2 - 4'x8'x4' deep fish tank with 1000 gallons and 4- 4'x28'x1' deep troughs. I am at a elevation of 6000 plus feet so I will loose about 24%. I was told by aquatic Eco-systems that I would need 2 Sweetwater S41 pumps at about 750 each. I live in Colorado and the wind is pretty much going allot of the time.
Can I use a windmill?
I also have an extra woodworking air compressor can that be used?
beware regular air compressors as they often have oiled parts and oil can get attomized into the air they put out. This would be very bad to send into a fish tank!!! There are ways I've heard of to catch the oil but I'm not sure how foolproof they are.
Also such air compressors are not really meant for constant running at high volume so it would probably be a very noisy and not energy efficient way to do things.
Perhaps you could use a windmill, Aquatic Ecosystems sells those too but you would probably need a backup for the times when the windmill wasn't functioning right.
Now air may or may not be the most efficient way to aerate a system. I use air stones and an air pump on battery backup but I'm only a couple hundred feet above sea level and can drive down to aquatic eco systems for spare air pump parts. I have a couple of their whitewater air pumps for my systems.
Another option for aeration is using a water pump to drive spray bars or a trickle tower or waterfall which could also provide some filtration along with the aeration.
All that said, Aquatic Eco Systems is probably giving you good advice. If you get diaphram air pumps, also get replacement part kits with them to keep on hand because if one goes, you don't want to go without while waiting for the part kit to arrive. Diaphram kits usually need to be replaced yearly. My two whitewater air pumps are different sizes but they both take the same part kit which is handy. In dusty situations, you might want to replace the air filter more often.
If septic systems in your area are required to be aerated, the air pumps sold for those may also work for aquaponics (I believe the whitewater air pumps were actually designed for septic systems originally, at least the manual that came with them gave me that impression.)
I'm not sure on the GFCI tripping issue. I had that one pump switch keep tripping the circuit in the garage but I can't be certain why. I have a different pump hooked to that same float switch now and it's been working fine for a year and a half. I make a point of putting that pump on a separate circuit but it hasn't been a problem since.
Any way you get enough aeration is fine and appropriate provided you get enough aeration where you need it.
Did you think about using a power head like this.http://www.thatpetplace.com/pet/prod/215156/i/1/product.web
I have one like that, it can pump 400g and you can hook up an airhose to the outlet without having to use an airpump and it will not lower your gallons that it will pump, when air is sucked into the outlet. You can use a tube in the inlet, drill many holes in it and wrap filter material around it. This powerhead was designed to use with an under-gravel-filter system, but it can be hung on the edge of the tank. I used it in a 50 gallon tank, but I never used it in a 410 gallon tank. Air-intake could be controlled with a little valve like thishttp://www.thatpetplace.com/pet/group/14346/product.web .
It uses 20 watts and it could run a few hours with a inverter(backup) on a lawnmower battery. You could make a set-up with a relay, when you lose power that it would turn your inverter on and that will turn your powerhead on or you could set it up where it would run with regular power and with the inverter in case you have a power failure..
Many years ago I used to work i a tropical fish store. We used those powerheads in 10 gallon tanks up to 150gallon tanks in addition to the regular systems. But we put a tube with drilled holes on the inlet and covered it with the blue filter material, which acts as a particle filter and a biological filter. This way we could avoid that the intake will clog up and in addition it would increase the biological filter without having to have a enormous filtration and/or pump system for the main pump-flow-system .
But the way I was thinking, that would be best in this case.
Put the power head with air-hose and air-valve in the sump tank, then pump the water/air mixure via pipes to the fish tank. The longer the air stays in the water and the higher the pressure the more air get's ' dissolved " into the water.
Is this theory right?
Would this increase the dissolved oxygen in the h2o faster, than air bubbles?
I installed a 1 micron filter on my shop air compressor just in case a problem occurs with the air pump. You could even go to a .01 micron filter but the price increases dramatically and more frequent changes will need to be done.