I have a planted aquarium that I've been working on for a while and I'm still trying to get my plants to grow nicely. From doing a bit or research, I believe that my aquarium plants may need additional iron. How can I get a small amount of iron to my aquarium plants? (without adversely affecting my clown plecostomus and ghost shrimp) Also, I don't have the money to purchase expensive fertilizers so a cheap or free way would be best.
Pushing nails or similar size bits into the gravel , make sure the are not galvanized. They will turn red/brown with rust fairly fast but being buried they will be out of sight. Another very fast possibility is putting a small bit of steel wool ( NOT with soap) into the filter system. You give me an idea; long ago I grew cryptocorne so well I sold it to a pet shop. That was in an angle iron tank and rust often fell into the tank. Since then crypt growth has only been fair in many different tanks; maybe they need iron.