Originally Posted by flapjax3000
The clay even under heavy misting retains it shape well. Several people on this board have made drip walls and ponds out of clay and experienced little to no erosion. My oldest viv that contains a clay based substrate is about 18 months old now, and I do not see any signs of the granules clumping. Just make sure to dig around as little as possible. The clay will press together very easily when wet.
One method I use that helps prevent the shape of the clay from eroding is to add Turface into the wet bentonite/red art clay mix before baking. The clay will bond to the Turface during the baking, yet still is small enough to be pressed through a screen.
As for the nutrient base, the frogs obtain calcium when a particle is stuck to microfauna and then eaten by the frog, not by the microfauna eating the particle and then passing the nutrient onto the frog. It is not like an organic substrate where bacteria and micro-organisms break down the organic material. Plants can potentially absorbed most of the nutrients over time, but I imagine by the time a clay substrate would need to to be replaced you be ready to change the viv anyway.
There are several routes calcium from the clay can end up inside the frog
1) through accidental ingestion while capturing or attempting to capture a prey item. The tongue is sticky and small particles of all kinds adhere to it. This also needs access to bare clay.
2) through accidental ingestion of particle stuck to the prey species
3) through particles that have been ingested by the prey species (clay can be ingested while feeding by invertebrates either accidentally or deliberately (as they need some level of calcium for their own metabolic needs)
4) deliberately by absorbtion through the skin (particularly on thier ventral side (thier drinking patch)). Not that the frog has to have access to the clay for this to work so covering all of the clay inhibits this...
Clay also fosters a microbial enviroment that tends to lock up as much of the nutrients as possible and this along with the continued influx of nutrients (dusted feeders, leaf litter, new plants) makes this unlikely that you decide to break down the enclosure based on aesthetics before you have to break it down based on nutrients. This does not mean that you cannot experience localized pockets of nutrient deficiency for the plants as nutrient input and cycling are not going to have as many processes as those seen in the wild for distributing nutrients but if that does show up it can be handled on a localized level without tearing down the tank.