This year, Pat thought it would be interesting to try aquaponics, and i said hey, why not - it couldn't be any worse than last year. And it wasn't, but not much better, either.

Materials list:

• Plastic rain gutter and attachments (elbows, joiners, end caps, etc)
• Lava rock to fill the gutter
• Half wine barrel
• 10-gallon plastic tub
• Water pump
• Automatic water trough filler
• A bunch of fish (we started with 24 goldfish)

For some strange reason, we never got pictures of this system. But to give an idea of the space it lived in, this is a picture of our greenhouse.

Inside the greenhouse, we zig-zagged rain gutter 6 times across the width of the dome. Our fish barrel sat outside of the greenhouse at the top, and a plastic catch tub sat outside at the bottom (both of which you can see in this picture.) Once every hour or two (depending on the weather), water from the bottom tub would get pumped up to the barrel for ~45 seconds, which was enough to cause the top barrel to overflow through a pipe, down a silly (but awesome) plastic trout-shaped spout, and into the top of the rain gutter. Since the greenhouse is on a slant, gravity helped the fish water flow down the zig-zag and into the catch tub. Very simple.

Because there was a lot of open area for evaporation to occur, the lower tub needed to be refilled frequently. So Pat went to a feed store and got an automatic float-valve trough filler, which would normally be used on a farm animal water trough. It's hung over the side of the tub and attached to a garden hose, and when the water level in the tub gets below a set level, it automatically fills from the hose, functioning much like a toilet tank float. After previously having to refill it manually almost every day (or forgetting, and finding our water pump having dry heaves), that was the best $9 we spent on the whole project.

So how did aquaponics work for us? Not very well. Go to any web search engine, search for 'aquaponics' and you'll find many stories about people using similar systems and getting great results. A nice collection of info and links about working systems has been put together by the ATTRA(Appropriate Technology Transfer for Rural Areas.) Usually these systems use tilapia instead of goldfish since they breed quickly and can also be used as food. But i think the issue for us was just one of numbers - we just didn't have enough fish making enough poop to provide enough nutrient for the plants. The plants were very stunted, their leaves quickly turned yellow, and if the fruiting ones blossomed at all, they either didn't set fruit, or the fruit was extremely small. Non-fruiting lettuce and basil did the best, growing very slowly to maybe 1/3 of their potential, but at least we could make use of a few of their leaves : )

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