I bought this because the water here is INCREDIBLY hard and even buying pre-filtered water doesn't do much. So I did a little experiment. I threw 2 tablespoons into a mesh bag and basically let it "cool" like a tea bag in a 5 gallon jug of room temperature water while I was at work checking before and after. According to the API GH/KH test, both GH and KH dropped from 125.3 ppm to 71.6 ppm in about 9 hours. It was still in the water and hadn't met my fish yet (I was concerned it would reduce hardness too quickly and my concerns seemed valid) but it's a definite difference nonetheless! Unfortunately I didn't check the PH beforehand so I can't tell if it has changed or by how much but I'm looking forward to reducing the hardness so we can put our fish in much better water.
KEDSUM 330GPH Ultra Quiet Submersible Pump With High Lift And Grounded Power Cord - Ideal For Fish Tanks, Ponds, Aquariums, Statuary, Hydroponics - Includes 3 Nozzles And 1500L/H Water Flow
39 Review
Sink filter Prio New Water Start Osmos OU380 white
79 Review
KEDSUM Battery Aquarium Air Pump: Ultra-Quiet Rechargeable Fish Aerator with Dual Outlets - Ideal for Fish Tanks, Outdoor Fishing, Fish Transportation, and Power Outages
35 Review
KEDSUM Quiet Rechargeable Battery-Operated Aquarium Air Pump With Dual Outlets - Perfect For Fish Tank, Outdoor Fishing, Transport, And Emergencies
28 Review
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
Mini pump Xiaomi Mijia Electric Pump 1S, plastic, black
55 Review
Steam cleaner Deerma Deerma DEM-ZQ610 EU, white/red
68 Review