I have been reading more about aquaponics and wanting to get into it, but I have been trying to do it without electricity. It seems like the two basic things you need electricity for are pumping and aeration. You can address aeration by dropping water from a height (I've also seen other ways to do this...I'll have to find those videos) but then you have to pump it back up.

Then I saw this video: ...and thought this would be perfect. Has anyone tried this?

Ram pumps and similar things can't operate in a closed environment. Takes a lot of stream flow to pump uphill, not sure how you'd get the fish water up in something like that.

Definitely looking forward to building a ram pump in the coming months for another project!

Scott is right. You need some kind of motive force for pumping. It doesn't need to be electricity. It could be a stream or (even better) a spring. It could also be a mechanical windmill. I've heard of people using a venturi for aeration.

Here's some info. on aeration from Nelson Pade.

Also check these out.

Here's my idea but it may not be the definition of aquaponics. Have minnows in a stock tank. Have a rainwater container piped in with a self filler float valve. Once a week, water the garden tomatoes with 25% stock tank water. The water level will refill itself. When (if) the minnows have babies, feed minows to the chickens. Its not closed loop system but takes 0 energy.

Thats the plan. I need to give some minnows to the chickens to find out. I bet they fight over them.

Right now i have the minnows in the tank. I have a bilge pump connected to a marine battery thats connected to a small pv cell like an electric fence would have. The bilge has a boat timer that turns it on 30 seconds/ off five minutes. Its been going 2 months now without losing the charge. The bilge areates and filters.

Great idea. One trick that will help over the long term is to have the overflow (watering) pipe come from the bottom of the tank so it can clean out some of the fish waste. Depending on your climate and how often it rains, you may run low on oxygen. Some fish (probably some minnows) are better in low oxygen than others.

To get significant fertilizer benefit from the fish you'll need fairly high stocking densities. The minnows, at least, will eat mosquitoes.

Ditto on the mosquito's. Dense population of minnows is not in the plan. I like minnows cause they have a use (fishing and chicken food assuming they reproduce). I'd never eat the tilapia, goldfish serve no secondary purpose.

If the water goes into dirt, the nutrient requirements are lower than growing in gravel.

Its a simple system that has a high probability of success. Success = high rate of continuation .

Yes. The water to garden is a water hose tapped into bottom drain hole of stock tank. So filling and draining are done with no pumps. Just gravity. Exiting water comes out of bottom.

Ram pumps and similar things can't operate in a closed environment.

But there are models, with a separation of the drive pile from delivery pile. So you could pump your water from your aquaponics system in a cycle, driven by a stream nearby. This might even be interesting, if the drive pile water was dirty, or in some other way not suitable to your fish. But usually, if you have that much of water running, it sounds at least as promising, to use the water flow directly to exchange the water in your fish ponds.
According to wikipedia efficiency of a ram pump is as follows:

dh : drive height - the height, you can use to drive the system. E.g. you have a natural fall of 2 feet.
ph : pump height - the height, you want to lift the water to. E.g. you need to pump from sump to fish tank for 5 feet.

vs : volume drive stream - liters of water per time running in your drive stream
vp : volume of pump stream - liters of water per time the ram pump can pump

e: efficiency - energy wise efficiency - might be as high as 0.8, but 0.6 is probably closer to what you actually get.

vp = vs * e * dh/ph

Assuming you have an aquaponics setup with around 15kg of fish in a cubic meter of water, and want to cycle at least once per hour. (some background data to flow rates)

in the given example this means you need a constant stream of more than 4 tons of water per hour, to keep your system pumped. ( 4000* 0.6 * 2/5 = 960)

There's also a raft aquaponics system, which if you combined it with fish that could either breathe from the air outside the water (off the top of my head I can only think of siamese fighting fish though I know there are quite a few more) or have very low aeration requrements such that they can be taken care of with a few competing plants in the water.

Now, raft aquaponics do not lend themselves to the growing of any plant that suffers "wet feet", so you would primarily be growing greens and very young plants.

Another option is carp, which can eat your food scraps and live on very little oxygen. The Chinese have used Carp in aquaponics for thousands of years.

If you'd like to eat them when they're grown, look up Vlad Janakovich on the Aquaponic Source Forum. He's from Serbia, where carp is a delicacy.