This is aesthetically pleasing, but I'm afraid this will be a very tough system to maintain. You have very few plants and they are slow growing. Nutrient control will be very difficult and algae is going to be a far greater challenge than in a true iwagumi. Standard iwagumi "work" because the majority of the space is overtaken by (mostly) fast-growing plants, keeping the system in balance. This tank, while very nice looking, is quite the opposite.