Today I started collecting things for my DIY Aerogarden, and testing out spray set ups. Here’s what I found:
106 GPH pump
I started my search at a local aquarium store, New World Aquarium at 38th and 3rd. It cost a little more than it would have online, but the salesperson actually knew things about it and could answer questions, so it was worth it. It’s about two inches tall and has variable output between around 45 and 106 GPH. It seems to push water through the tubing/misters nicely.
Various hose bits
I stopped at the local hydroponics store to get some T joints for my hosing, and some sprayers as well. The sprayers attach to 1/2 hose pretty easily, just cut a small hole in the hose and push the sprayers in.
I also picked up some rockwool and plant nutrients, so make my own “seed pods.” The bag of nutrients was $18 for more than 2 pounds of dry mix, which gets mixed with water at about 1 tsp per gallon. My garden will probably hold about a quart. So it should last me quite a while. The rockwool is $7.50/48 cubes, and I’d need a max of 1 cube per planting (tho I plan on using half, they’re big cubes).
Hosing with misters
I ended up using a circle of 1/2″ hosing about 6″ in diameter. The four misters are placed relatively evenly around it. The bottom of the T joint goes to the pump.
The misters I got are a little more like sprayers than misters, the water coming out isn’t very fine. I’m not sure if this is a function of water pressure or the type of misters I got, I think the latter.
I ordered some different misters from Drip Depot which are supposed to produce a “very fine mist” so we’ll see what difference that makes. Luckily all this stuff is really cheap, the hosing I can get at the pet store down the street, and the misters/connectors are all under a dollar each.
Here’s my pump/hose setup in the planter I got from the dollar store. There are two problems. One, it’s not tall enough. The planter has these “feet” which make it look taller than it actually is. I want at least 2″ from the top of the sprayers to the top of the bucket. The hose connectors add a substantial amount of height to the whole thing.
I ordered some L connectors which would allow me to put the pump on its side, but I think that would give me an extra 1/2″ at best.
But the real problem with this planter is that it leaks. Sure, it *looks* sturdy and without holes, but there are thin spots in the plastic near the bottom where water started eeking out. No good.
So tomorrow I’ll go in search of a more appropriately sized leak proof bucket. Once I have that I can start working on the top part to hold the plants and deal with lighting.
I’m no expert…working on it but not yet…but I think your mist needs to be between 5 and 50 micron droplet size. We’ve gotten most of our information on this from Wikipedia and branched off from there.
http://en.wikipedia.org/wiki/Aeroponics
I’ve seen large growing operations using what you are putting together here but the system has to run full time in order to get the plants the nutrients they need. With smaller droplet sizes you begin to get the benefit of capillary action and osmosis to immediately pull the droplets through the cell walls of the roots causing more moisture uptake in a shorter amount of time.
Anyway, keep bloging your progress. We are really interested to see how things turn out and learn from your experience.
Demented
Yeah, I think you’re right about the water droplets being too big in this model to be “true” aeroponics. Technically I guess it’s more of a drip system?
The airstone version produces a much much finer mist – I actually can’t really see it – but at a much lower rate, so both systems will probably have to be running all the time. But our living room already has an aquarium and 4 computers, so I don’t think one more motor will disturb our “tranquility.” 😀
Once I get the systems to a point where I feel like they’re working I’ll set up some tests vs a commercial tabletop system like the AeroGarden.
Looks like a good approach. I’m trying to find the basics for a system that can be put together as cheaply as possible AND be reliable. The 5 micron drop size sounds right. The humidity has to be 100% or close at all times and you don’t want to get it too wet or you lose the root hairs.
Can your pump handle on/off at 5 – 15 min intervals and not burn out?
Some news you can use – look into mycorrhizal fungi. They’re symbiotics that get nutrients across the root cell wall with much great efficiency. I use them in my outdoor garden. They’re awesome. Try Espoma Starter mix. In ground, they’re an order of magnitude amplifier. If your purpose is for transplanting then be sure to use this when you add soil.