Have been using them for 4 months with a cheap dispenser from here. Use of black premium airlines. There are no check valves. So far no problems! Soft corals are larger and hard corals grow well. I did daily water tests for 2 weeks to roughly measure my daily intake and simply used formulas to replace that amount plus 5% in 6 steps throughout the day. Works perfectly. 25% water change every 2 weeks. Using Red Sea Coral Pro salt. See my review for another part for a picture.
Jasonwell Magnetic Aquarium Fish Tank Glass Algae Cleaner - Floating Brush (L Size)
37 Review
Greenpro Micranthemum Monte Carlo: Live Large Pearl Grass Aquatic Plant In Tissue Culture Cup For Freshwater Fish Tanks And Aquariums
49 Review
Steam cleaner Deerma Deerma DEM-ZQ610 EU, white/red
68 Review
Efficient 2-In-1 Magnetic Fish Tank Cleaner With Non-Slip Design And Scratch-Free Blades
37 Review