I have never tested water for evaporation in cosmetics and have never had a problem. Then one day adding a liter to a 5 gallon tank was fatal to all fish! The water company did something and the pH of the tap water was over 9.0! Two days later back to normal, about 7.1 pH. These test strips are needed every time. You can never be sure the water company isn't cleaning the lines or whatever. Be safe for your fish, always check the water.
FUNSWTM 7 in 1 Aquarium Test Strips: Accurate Water Testing for pH, Nitrite, Nitrate, Chlorine, GH & KH Levels
8 Review
🧪 Enhanced API Replacement Test Tubes with Caps - Ideal for API Freshwater Master Test Kit - 24 Count Box
8 Review
Highly Efficient Seachem Purigen for Freshwater & Saltwater Filtration
9 Review
🌊 Hanna Marine Alkalinity Checker HC - HI772: Accurate & Efficient dKH Measurement
9 Review
Vacuum cleaner TEQQO Aquastick 3 in 1 Power, grey/turquoise
26 Review
Efficient 2-In-1 Magnetic Fish Tank Cleaner With Non-Slip Design And Scratch-Free Blades
37 Review
Steam cleaner Deerma Deerma DEM-ZQ610 EU, white/red
68 Review
Greenpro Micranthemum Monte Carlo: Live Large Pearl Grass Aquatic Plant In Tissue Culture Cup For Freshwater Fish Tanks And Aquariums
49 Review