I see value to active substrates for beginners as it will compensate for errors during the learning process, but I donít want to have to start guessing with problems due to the inevitable fluctuations from various degrees of nutrient exhaustion due to a dying substrate, even if it can be given life support for an additional year or so. In the case of ADA AS, doesnít it, essentially, turn to mud in 3 years or so, requiring full replacement?
I have to say that I am also not a fan of root tabs. As mentioned in my post, I strive for consistency and root tabs are not predictable enough, IMO, to satisfy my nutrient consistency goals. All nutrient needs by virtually all plants we typically see in our hobby can be serviced by water column dosing.
I agree that aquasoils are easier for beginners. They can definitely build up a good amount of mulm and experience some breakdown, but I think a lot of the "mud" that people experience with aquasoils are due to never gravel vacuuming/cleaning the substrate. Felipe Oliveira and Dennis Wong both have good videos about cleaning aquasoils.
I can't comment on the longevity of aquasoil. I haven't had it turn to mud, but I also haven't had any aquasoil tanks for more than 3 years due to the frenetic pace at which I rescape my tanks.
Root tabs are a valuable tool IMO. With water column dosing, you just have to hope that your plants, as @Greggz
likes to put it, "like the soup you're serving." Root tabs allow you to target dose certain plants while keeping the water column lean for others. In terms of consistency-- well my plant mass varies greatly from week to week and throughout the week as things grow. I probably take close to a pound of plants out of my 22 gallon every two weeks. The nutrient demands of the plants are constantly changing, so I am not so worried about making sure the amount being dosed is consistent so much as watching for deficiencies and addressing them as needed.
It seems like you've been in this hobby for a quite a bit longer than I have and therefore think of things at a longer time scale with regards to substrate lifespan, consistency etc. Not trying to say you're wrong, just that we have different approaches.
That Peace River gravel looks pretty perfect. As I mentioned before I struggled with BDBS and I think part of it was limited root growth due to compaction/small grains size and a lack of circulation in the substrate. I'll have to try that out next time I try an inert substrate!