Like many of you, the hum of the 6 pod unit annoys me quite a bit. I decided to hack my Veggie Pro a little bit and use a super quiet Rena air pump. I've documented it here just incase anyone else is interested.
Here's all the materials needed.
Bottom right is the Rena air pump. The Rena Air 200 model is the smallest pump that Rena offers with an adjustable output. It is extremely quiet and has a pretty decent output. It's a little more expensive than other pumps but I think it's well worth the price. I found one for $32.99cdn online.
Top right is silicon tubing. Silicon is a little more expensive but it won't foul up in nutrient solution. Standard airline tends to get milky white after a while... I'm not even sure if that's a bad thing but I had some silicon tube in my junk box so it's getting used.
Middle is a Rena Micro-Bubbler. It is a ceramic airstone that produces a lot of very tiny bubbles. Ceramic airstones definitely last a long time if you take good care of them.
Top left is a couple of suction cup loops for holding the air stone.
Bottom left is a check valve. You may use one of these guys if you are the paranoid type. The aerogarden already has a back flow prevention scheme in place so adding a check valve is redundant unless you plan on not routing the air line along the arch in the nutrient reservoir.
Unscrew the 8 screws in the bottom. 6 of the screws are philips and two of the screws are special Tamper-Proof (also called Security Screws) Torx 15. You should be able to pick up the bit at Home Depot.
This is what the guts of the Veggie Pro look like. Power supply on the left, controller board in front and air pump on the right.
Peel back the tape holding the air line down and lift the air fitting. Be careful not to lose the gasket. Remove the fitting from the air line. I made a cut along the barb to make it easy to remove.
Remove the pump and cut the wires. Cut the two wires at different lengths and wrap the ends with electrical tape. Shove the wires back into the grooves so they aren't flopping around inside the base.
Drill a 1/4" hole in the back of the base.
Feed the new air line through the hole and plug the air fitting into the end. Secure with the tape. Mark the hose with a felt pen right where it enters the base so if it get's yanked on, you know how far to push it back in.
Remove the existing airstone from the arch support. I used a utility knife to cut the hose lengthwise along the barb to make it easy to remove.
Install a new length of hose and attach the new airstone. Make sure to follow the arch with the hose or you will leak water whenever you lift the reservoir from the base.
This air stone works well but I don't really like the way it sits. I think I'm going to try to get my hands on a Deep Water Innovations Micro-Pore Air Diffuser which will fit in there without the extra loop of hose because it has a barb at the center of the bar.http://www.deepwaterinnovations.com/Products/MicroPoreOxygenDiffuser.aspxUpdate
: Put in the Micro-Pore airstone and I couldn't be happier. It really is a quality product. Free flowing and ceramic so it won't break down.
This shot shows the new airstone working. The picture doesn't really do it justice. There is substantially more aeration and agitation. If the bubbles make too much noise, I can adjust the pump output so I don't hear a thing.
Here's my happy little herb garden after 20 days. If you don't have carpet near your garden, I highly suggest you get a little square of carpet to sit the pump on... it really cuts the vibration.