56 days in and many of my lettuces are bitter. I can see pencil thick stalks with slightly smaller leaves growing off of them. Too late to lower nutes because I just had a reminder yesterday. I had three pods not grow at all and Aerogarden replaced them for me. I guess I will have to use those pods after I take all these bolted ones out. I keep my house at 78 degrees part of the day when we need to conserve power, so maybe too hot for them. The lettuces were nice for a while.
That is a long time to have lettuce. I'd say you did good. Did you try popping in some ice cubes each day to keep the water cool?