When I was in socal I was part of a bigger club so I would time pulling plants with a day before the meetings. You can then auction it off for cheap or hand people stuff. Plus I had two stores who I could trade with for store credit. I only really grew frogbit, jungle val, dwarf sag, swords and Hornwort back then. I had liquid concrete out the tap and no C02.I wish I had a better answer but here's the truth.
I've been keeping this tank for a LONG time. And it grows like mad. Some plants literally do grow almost an inch a day and I guess over the years I've grown numb to trying to find them a home.
So I do throw out a pretty massive amount of plants. I'm really not interested in selling them, but do give them away from time to time........but the reality is as sad as it is most just get unceremoniously tossed.
Like I said with I had a better answer!
I hope as my tanks mature I can do the same here. One store is very interested in my Xmas moss. My Java Fern Narrow Mini have tons of plantlets on its old leaves I am sure they will be in demand as they grow.