Caribsea eco complete fine grade planted aquarium substrate is one of our most popular products and no wonder its brilliantr a finer grade gravel than the standard eco complete product at 025 3mm grain sizer contains iron calcium magnesium potassium sulfer plus over 25 other elements to nourish your aquatic plantsr eco complete planted aquarium substrate contains all the mineral nutrients needed for luxuriant aquatic plant growth without nuisance algaer the eco complete is iron rich