what had been done?
An decent no filter / no air pump old fish planted tank recycled. All planted removed, soil had been strongly washed by tap water in order to bring up all mud and dirt in the bottom.
I don’t need too much soil for the new setup, so I removed 2/3 thick of the old soil. Then a hang-on filter did all the rest from the mud water into clear water, without changing any water during the period.
So once again, do not believe anyone who hard selling his “Best” soil. Any kind of soil CAN be crystal clear depend on how you handle it. No matter what brand….