But where's the Bristle Noses?!?!
By the way, how do they like the Repashy Morning Wood?
I haven't tried that formula yet (primarily use Soilent Green for my algae eaters).
I don't think BN (ancistrus) eat much wood though, at least not nearly as much as the main wood eaters (Panaque).
Oh yeah, have you tested to see if that slate is raising your pH?
I bought similar looking slate from Home Depot (was planning to make pleco caves as well) and tested it several times for over a month, even scrubbing it down a ton, and it still would leach metals raising the pH.
I know most slate is inert and supposedly safe, but if it has any metallic streaks (I think the red patches even are iron deposits?) then it will leach metals and is therefore not inert.
But you tanks looks to be doing well (at least plant wise) and it's been a while so I assume it's alright. Might be leaching, but your plants and co2 might be countering/reducing it.
By the way, I think breeding plecos much prefer closed end caves (so they can guard the cave/fry/eggs) rather than both ends having a opening.
Take much string to tie down that Riccia?