Do you guys use soil test kits to test the pH of your soil? I'm talking about for emersed cultures. Either way, what pH do you generally aim for in your soil mixtures for the average Crypt, and then what about for the black water crypts? What changes do you make? I guess most people would just add more peat of some form, or leaf litter if they have access to some, or both.
Generally speaking, when making a soil mix for your Crypts, I would suggest you try adding some greensand, aka glauconite if you can get any. Not only for the Fe and trace minerals it contains, but also for the particle size, since I find that Crypts tend to like having some sand, or sandy loam of some sort in their soil, probably because it helps provide support for young roots. Adding a little bit of MTS or EHS will go a long way as well, and if you are growing Crypts submerged, or any heavy root feeder for that matter, you should hit up Hydrophyte and see if he has any of those soil tabs he was making, and try those out, cause the plants will really like having that organic matter, and I think they had a good amount of humic and fluvic acids as well which are great.
As for ferts, you can always add some Osmocote Plus. I forget who, but someone was making clay pellets that were basically like little Iron tabs and they were really small so they were easy to work with, but I don't really grow my Crypts submerged, I have only three different Crypts growing submerged right now, and I don't really like Echinodorus, though I have one that I'm thinking about switching to emersed growth, and I also don't like keeping super densely planted high-tech tanks, cause I can't afford it and I don't have the time or patience to do all that maintenance in my free time. I have nothing against them, I think they're great, and beautiful, and I appreciate them for what they are, and I have a lot of respect for anyone with a well-scaped high-tech tank, but I just personally don't have the patience for it. Therefore, I've only used root tabs submerged like once or twice. But now that I'm thinking about it, it's definitely time to add some new root tabs after I change my water and thin out my tanks. Ughhhh, I gotta stop procrastinating and get on that, I've got a lot of work to do today