ATN: Those using coal slag, I have a question!
I am going to replant my tank using a finer substrate than Flourite and want something black. Also wanted to avoid sand. I would've liked to get some ColorQuartz but its not made anymore so the next best thing is likely 20-40 or 30-60 coal slag.
Anyway, my question is this: do you find that the iron content is high enough in coal slag by itself or do you have to supplement it with something or make up for it with dosing iron? I'm having a hard time finding info on how well it holds nutrients also, does it do a fair job overall? How does it perform? I'm also thinking of leaving an inch thick layer of Flourite under the coal slag. I'm not sure of my logic on that last idea, I just like it I guess.
If anyone who has used or is currently using coal slag could contribute pictures or experiences, I would greatly appreciate it!