I am not one to clean the substrate much - certainly not around the plants were I expect any roots to be. I cut the Jobes in bits - 1/4 or 1/2, don't remember which - and put them in the substrate next to the swords. I don't think they were dug up, or at least I didn't see it, and the fronts were a lot smaller then. I did, however, put some bits of the Jobes into the roots of the Java fern that's attached to the background, and they probably leached fertilizer into the water column. I didn't think it would matter much, because I used only like 2 sticks for the Java fern, and I have about 300G of water in the system. It now seems that this caused a bit of an algae bloom - nothing drastic, just a lot more pesky hair algae on the background that I had to pull out manually.
Regarding traces, that is good thinking, and I admit that it hadn't occurred to me that this might be a problem. To give truth the honor though, the carbon block filter should be changed every 6 months, and I haven't done that in 2 years, so by now it's unlikely that it's very effective. Also, wouldn't the crushed coral supply trace elements? Still, I might get myself a bottle of Flourish and try that out.
Regarding N and P, you are quite right, Rex, I should probably check those occasionally just to make sure my assumption is true. However, intuitively I'd say with 50 fronts in that tank plus plenty of other cichlids and catfish, they gotta poop something, and I'll be darned if there isn't some P and N in there
Now about the K, when you guys dose K fertilizer, what kind of concentration are you shooting for? If I knew that, it would allow me to calculate how much potassium I should add. Of course I'd start with a modest amount and increase the dosage if required.
BTW, Rex - that is some fancy logo your local fish club has, and seems like a hard-core kinda organization judging from your signature