Vlad, currently I have eleven 13-gallon air root pruning containers, that I have planted in ReptiBark 5-2-1, all new re-pots in the last 10 days. All are looking extremely healthy, and currently in an additional flush. Like you suggest, I could extend the interval between watering by 2 or maybe even 3 days. However, as root zone moisture decreases, the energy out put required by the tree to extract enough water increases. Of course as the summer fades into fall and winter, the intervals in between watering lengthen. Using a 5-2-1 medium there is not much worry concerning the perched water table. Therefore, for these 11 trees, I prefer to keep them closer to this stress free schedule. It is not so much the amount of water that causes root damage, as it is the lack of root zone oxygen. This type of watering can only occur with rapid draining mediums. I add the Calcium Nitrate as the water used is rain water. As always, the best to you and your trees.