What is the reasoning for you wanting to slowly decrease perlite? fwiw I was originally going to slowly increase perlite. e.g. clones in beer cups of 100% coco, then into 1 gals with 90% coco 10% perlite, 2 gal with 80% coco and 20% perlite. but to be honest seemed like a lot of extra effort and too many variables/Wow great thread. I was thinking of doing very similar to you blackcat. I was going to root in 50/50 perlite coco, pot into 1 gals and slowly decrease the perlite till finally potting in 100% coco in ten gals. Was hoping then to just water one or two times a day. I have only done just coco, but never have tried big trees. I know another grower that just did lots of perlite and a little peat reserculating drip that really worked well. This thread has me thinking. I like to hand water, but I definetly think an airier mix with more watering would be better.
I think we'll try 50/50 coco and chunky perlite for the first run. should allow us to water frequently i.e. every day.
thx for the link on that air diffuser. and the info about the heavy metals.lol air line will work pretty well i think