Test Kits & Monitors Water Testing Guides
Reviews and comparisons of aquarium test kits, digital monitors, and smart sensors. Know your water parameters before problems start.
You can't manage water quality you can't measure. Ammonia, nitrite, nitrate, and pH are the four parameters every aquarist needs to track — daily during cycling, weekly once established. A liquid test kit like the API Master Kit is the baseline. Digital monitors and smart sensors add continuous tracking without manual testing.
Saltwater tanks require additional tests for salinity, alkalinity, calcium, and magnesium. The guides below cover both manual test kits and digital monitoring systems for freshwater and saltwater setups.
Guides & Reviews
Test kit reviews and monitoring system comparisons for freshwater and saltwater aquariums.
Best Aquarium Monitoring System for Freshwater Tanks in 2026
The best freshwater aquarium monitoring systems compared — from smart WiFi multi-parameter monitors to temperature controllers, digital thermometers, and manual test kits. Reviews of Kactoily, Inkbird, Seneye, API, and VIVOSUN.
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Best Saltwater Aquarium Test Kits for Reef and Fish-Only Tanks
Compare the best saltwater aquarium test kits for reef and FOWLR tanks. Reviews of API Master Kits, Hanna Checkers, refractometers, and digital meters — plus a testing schedule and buying guide.
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Testing tells you what's happening. These guides help you fix it.