All four of the Harvests are hooked up to Pulaco Aquarium Air Pumps. Two amber Mason jars are hooked up to the AP420 air pump. I have considered disconnecting the air pumps, except that I believe bubbling air through the root system of my only AeroGarden Mini Jalapeño pod (in the jar named Grit) is what saved it.
However, I have 14 seed pods in three AeroGarden Harvests with aeration and none of them have germinated. I can't tell if it does any good in Harvey - the two AeroGarden Red Fire Pepper plants there have been producing all along, with or without air. Phredd and Ethyl have bountiful lettuce crops with no air bubbles. Phredd even has that tomato plant that's doing well.
Aeration is not without petty annoyances. Rubber tubing will not slide on the tubing connectors. I've tried the soap and vegetable oil tricks. That means that at some point, every bit of tubing has slid off every connector., including the air stone in the system, underwater. I have two different Kratky air adapters. The first - the one in use in Grit and Fredonia shown above - has an offset hole for an AeroGarden or iDOO seed pod and a hole large enough for the tubing. The second (arrived yesterday) has a center hole and a smaller hole for a fitting. The intention is to have a small section of hose connected to the air stone on one end and a U-connector through the cap at the other.
As shown at right, the "U" connector sits flush on the lid, minimal interference with the plant. The connector provided is too fragile. I've broken two out of three trying to attach the tubing. Fortunately, I have a supply of elbow connectors and in-line connectors that work just as well (better, but that's a matter of informed opinion.)
I suppose I could test whether the aeration is bad for the Harvests by simply turning off the air pumps. There. Done.
Aeration continued to Fredonia and Grit. The Romaine lettuce in Fredonia grew to amazing heights, leaning over into Sheba's space to soak up even more light, so I harvested it and planted a Marvel of the 4 Seasons lettuce seed pod. The AeroGarden Mini Jalapeño in Grit also continues its recovery and new growth.
The only change visible in Harvey Too, Seble, and Teresa is that the new seed pod in Harvey Too - a generic pod with two seeds from an Amazon order (mini bell peppers) - have germinated and grown enough to require removing the hot-house dome. If that pod could grow so quickly without aeration, why haven't the others with aeration?