UNH?
Do you mean UNS Controsoil
ultumnaturesystems.com
Glass Aqua site is worth a thorough read, as they’ve been scaping with various soils for awhile now (I love their photography and Shop the Look scape designs, FB page is great for following their scapes)
Fresh water aquarium installs in the Southern California area. We cater to all different types of budgets service private homes and commercial spaces.
glassaqua.com
I’d also look to Aquarium Design Group (I believe they’ve been using Tropica and UNS (and maybe Aquario) products as they too have experienced the ADA North America distribution game)
I think that all of these engineered aquarium soils offer great ease and stability ... I’m a fan of Tropica Aquarium Soil as it holds up well over time but look at the pricing
I’ve not used the UNS or Aquario soils (more expensive at my lfs, and I still have loads of Tropica)
ADA Amazonia is much more prone to mudding than Tropica so if you’re looking to clean and reuse soil I’d avoid ADA
(also if you’re likely to move plants etc about, especially with livestock in tank)
Fluval stratum is absurdly expensive locally, but more importantly it has had quality control issues (killing shrimp, stopping shrimp breeding)
If you want to use EC as a base layer, I’d place it in fish media bags (or those mesh laundry bags for “delicates”) so that it remains separate from your aquarium soil (unless you’re OK with it mixing)
For building height, look for a local material that’s similar in size/structure to ADA Power Sand (that seems like it was some translation error as it’s completely un-sand-like) as it provides excellent “flow”
If you’re planning to have this single scape and keep it for several years, I’d likely invest in some nutrient rich base layer such as Tropica Growth Substrate etc (or some combination of Tropica GS, ADA Power Sand (especially if you want some deep substrate areas), and also plan on using root tabs (Filipe Oliveira is the master of root tabs in his set up/rescape videos)
I’d only use sand for decorative purposes or if you’re wanting to keep certain fish species (many dwarf cichlids seem to benefit from sand for long term health)