I have been using 3-4 mm size, but just bought medium 8-9mm size and think it is too big for what I want, I have various sizes of trees so anybody know is there some rule of thumb to use? per height or trunk size?
For anything larger I will go 1/8” to 1/4”. Whether or not to leave in the 1/16” on these depends on how much water retaining capacity I’m aiming for. I take it out for trees like Ponderosas, leave it in for trees like deciduous.
Careful using it for drainage layer. I think it would degrade and plug up the bottom.
Maybe 50-50 with equal size lava or pumice but I would NOT use akadama as the entire bottom.
(actually I try to keep the stuff from anywhere near the bottom)