@Randy Holmes-Farley I'm considering using Seachem Iron Flourish. It is more concentrated than most iron products. A 500ml bottle contains 5000 mg of iron gluconate. (10x the iron content of Brightwell's Chaeto Grow). However following Randy's DIY usage, I also have a 300 gal tank, I would add 0.1ml twice a week. Therefore I intend to dilute Iron Flourish further in distilled water to make the dosing more manageable, likely 10-to-1. I assume this approach is not an issue, the iron gluconate will remain is suspension?