Black Diamond/Manure/Red Clay, STS Substrate?
I've been reading up on substrates and CEC rates, and I'm considering mixing a custom blend and wanted to pass it by you planted tank gurus, since I have no practical experience with planted tanks. I sure would appreciate some input.
First of all, my primary goal is purely aesthetic, and for that purpose I choose to use the Black Diamond blasting sand (medium, 20/40 is what I've seen suggested, right?) for its ease of use, long-term neatness and appearance. Of course, it is inert, so root tabs must be used with it alone and seem to be a second choice option as far as growing plants is concerned. That is where the cow manure, red clay and Saf-T-Sorb come in, cow manure for the long-acting availability of nutrients in humus (<10% in the mix), red clay for the availability of usable iron content (~10%, is this right?), and Safe-T-Sorb for its high CEC and ability to stay together better than cat litter or similar products (% to be determined).
Of course, with the manure I will be expecting an initial ammonia spike when first submerged and plan to allow the nitrifying bacteria in a "seasoned" filter to catch up and let all ammonia, nitrite and nitrate levels settle down before adding plants (is this necessary for just plants?).
Also, I plan to run the system as low-tech with no added CO2, but with a lighting "rest period" during the middle of the day to allow CO2 levels to catch up. I have no problem dosing fertilizers regularly, especially since the CEC will pull them out of the water column initially.
Am I on the right track here? Will adding these ingredients to the Black Diamond significantly increase the "messiness factor" when pulling old plants out and planting new plants? Any comments or suggestions will be appreciated.