
Most of these chemicals neutralize chlorine in tap water. It also neutralizes nitrates, nitrites and ammonia. Neutralized ammonia does not harm the fish, but can still be used by bacteria in the aquarium. About the best you can do. I don't use anything anymore. Cheaper brands won't do any of this.

Tetra AquaSafe tap water treatment agent, 5 l
11 Review

π API Stress Coat Water Conditioner | Tap Water Safe, Repairs Fish's Protective Coat, Use for Water Changes, Adding Fish, and Injuries
9 Review

EcoBio-Block Stone: Natural Water Clarifier & Odor Remover for Aquariums (Medium) - Treats 15-40 Gallons Efficiently
10 Review

12 Count Greenpro Root Tabs Fertilizer Tablets: Ideal For Aquariums, Ponds & Water Gardens!
26 Review

π§² Efficient Magnetic Fish Tank Cleaner: KEDSUM Floating Clean Brush with Handle Design
34 Review

Mini pump Xiaomi Mijia Electric Pump 1S, plastic, black
55 Review

Greenpro Micranthemum Monte Carlo: Live Large Pearl Grass Aquatic Plant In Tissue Culture Cup For Freshwater Fish Tanks And Aquariums
49 Review

Jasonwell Magnetic Aquarium Fish Tank Glass Algae Cleaner - Floating Brush (L Size)
37 Review