A couple of years ago my daughter gave me an AeroGarden for my birthday. My plants grew like a charm. First, I grew peppers and then I grew tomatoes and I even grew herbs.
Then . . . I moved.
When I set the AeroGarden up again it just didn't grow very well. I thought I had damaged it during the move. I changed the water and scrubbed out the basin. I replaced the air stone. I checked that the pump was working. The lights looked fine, but my plants still weren't growing as they should.
I planted new seeds in new pods.
My seeds didn't germinate well and when they did, the plant growth was stunted. Many of the leaves developed brown margins.
I was puzzled, until I visited the AeroGarden site.
According to the site, my well water might be the culprit. Apparently hard water can prevent germination and cause both stunted growth and browning leaves.
Once again, I emptied the basin and scrubbed it clean. This time I filled it with filtered water. Within days my seeds germinated and showed signs of vigorous new growth.
I am growing petunias and lemon basil in it now. I can't say for sure how long ago I planted the petunias as I forgot to reset the 'days planted' counter. I know that I planted them after Christmas. That means they can't have been growing longer than 40 days or so.
I am so excited to have solved the problem and to have petunias blooming inside as the snow falls outside!
If you are having issues with your AeroGarden, or similar hydroponics unit, try using filtered water instead of your well water. It solved my problems. I hope it solves yours too.