You and others here have gone crazy on this subject. To hold a burrow any sand or dirt only needs to be moist. Store purchased sand is screened into uniform sizes, therefore, it does not hold a burrow or moisture to well. Do you understand that? Fines or small dustlike particules are what allows sand to hold moisture and as a result, a burrow.
Also, you going all out trying all sorts of stuff is a tiny bit ahead of the game. The first thing you need to do is, provide a good enviornment for your monitors, good temps, methods to not allow dehydration, good food, good selection of hiding areas. With these, your monitors will soon grow to adults. Great burrowing conditions is not needed for babies, in fact, behaviorally is not a great demand. All the other stuff is.
Burrowing becomes very important(a matter of right or wrong) during reproduction(nesting) up until then, it not all that important. Non nesting ackies will choose cracks in rocks, cracks in trees, digging under flat rocks, or concrete or anything that will help hold a burrow. Mind you, thats in nature. Of course in areas without the those things, the only option is to make a burrow. Ackies often live in areas without rocks and trees and garbage piles(tin, wood, concrete, old metal water tanks) they often use roots from plants as a method to "hold" a burrow. In places that there are few in any plant roots, they will use rodent or marsupial(mice) burrows.
Please understand, even in nature, dirt may not hold a burrow ALL ON ITS OWN. In many cases, if the area they live in has soil that does not hold a burrow, they will move to other areas for nesting, this is normally around washes where the moisture levels are much higher, therefore the soils hold burrows better. In areas of blowing sand(sand blows in Oz.)(sand dunes here) they cannot burrow in loose sand, so they only live in the areas with the sand becomes mixed with other soils(hardpack) and holds burrows or use the aid of spinifex roots.
Normal natural ackies may burrow for long periods, mainly because the weather conditions forced them too. Otherwise they perfer to live close to the surface. In our cages, they normally prefer to live on the surface or above, until conditions force them underground. These conditions are, too hot, too cold, too dry, not enough food, etc. When conditions are bad, monitors and most other reptiles do not take a plane or a train, or even a bus, consider they have no cars, they only understand to drop down and hide, that is, to burrow(into a suitable mass) and wait out the unsuitable conditions.
Unsuitable conditions, causes a need to burrow. I hope this is not your case. Which exposes the opposite, if conditions are good, they may not have a need to burrow. In that case, whats your problem going bonkers over finding something good to burrow in??????????
Please understand, digging is a good form of exercise, so is climbing, and walking and running. Many people here keep them in little tanks, with one hide, ugly half round piece of wood, or plastic rock, a water bowl and indoor outdoor carpet. In these cases, digging dirt is the only option for exercise, ITS VERY NEEDED HERE. From the pics of your cage, you have all sorts of stuff to climb, jump, run, etc, on. So why the worry about dirt? I would not worry until you suspect one is gravid. Please reread this many times, then find a book, one of many, that show ackies in nature and their habitat and read them. Many give discriptions of many kinds of kind a certain species will live in.
What your doing is very normal and you will see it time and time again, here on KS. What it is, is, inexperienced people take many things, out of context, they do so because, they have no other idea/s of what is correct. So they beat a carrot to death.(you with the dirt) As you may already understand, a carrot has nothing to do with keeping monitors. Its out of context.
As you see, many people here use me as the "carrot" they beat on me, because they have no idea or experience with what suitable to do. But as you now know, I(the carrot) have nothing to do with them or their ability to keep monitors successfully. I am simply a carrot and beating on me, will not effect their ability or understanding of monitors, this goes for beginers all the way to MS's. So please, keep your efforts in context, the sand, dirt, substrate, is important, just not that important. Keep it in context. You can raise happy healthy ackies without dirt. Don't let the dirt stop you. It may only be a carrot. FR
