We do not run a water lab. This page compares what the boxes actually test, how you read them (drops vs dip), and which job they are for: cycling vs a stable tank. If you are still in the 4–8 week nitrogen cycle, read How Long to Cycle a Fish Tank first — a kit you cannot read ammonia on is the wrong kit for that job.
The parameters that decide whether fish live: ammonia, nitrite, nitrate, pH. GH/KH matter for shrimp, livebearers, and African cichlids. Strips that skip ammonia are fine for a later weekly glance. They are not fine for a new tank.
How we ranked
- Does it measure ammonia (the first toxin in a cycle)?
- Method — liquid reagent vs strip vs one-parameter refill.
- Published test count / what is in the box — not a durability lab we invented.
- Job — cycling, weekly check, or planted/shrimp extra.
The 5 kits
1. API Freshwater Master Test Kit
Best for: Almost every freshwater tank. First buy.
Liquid tests for ammonia, nitrite, nitrate, pH (and high-range pH). API publishes on the order of ~800 tests per kit. This is the kit the hobby points at because it can show ammonia during a cycle, which most strip bottles cannot do well. Color-matching is the skill; do it in daylight, not RGB phone flash.
Watch-out: Not instant. Budget 5 minutes. Reagents expire — write the open date on the box.
2. API Ammonia Test Kit
Best for: Cycling on a budget, or a second bottle by the quarantine tank.
Same liquid ammonia chemistry as the master kit, one parameter. If you can only buy one test this week and the tank is new, buy ammonia. Add the master kit when you can.
Watch-out: It will not show you nitrite/nitrate. Do not declare a cycle “done” on ammonia alone.
3. API GH & KH Test Kit
Best for: Shrimp, livebearers, rift-lake cichlids, or mystery pH swings.
Drop-count GH and KH. This is the kit you add after the master kit, not instead of it. KH (carbonate hardness) is why pH crash shows up after a heavy rain of RO water or a forgotten water change.
Watch-out: Useless as your only kit. It does not see ammonia.
4. Tetra EasyStrips 6-in-1
Best for: Fast checks on a tank that is already cycled.
Dip strips for nitrate, nitrite, hardness, chlorine, alkalinity, pH — in about a minute. Useful when you already know the cycle is done and you want a cheap weekly glance. Published hobby comparisons (and basic strip chemistry) keep showing the same hole: ammonia is the weak pad. Do not cycle a tank on these alone.
Watch-out: Humidity kills a strip bottle. Close it. Do not use a faded card.
5. Salifert (single-parameter liquid kits)
Best for: Planted tanks and anyone who already owns a master kit and wants a tighter nitrate or phosphate read.
Sold as individual tests, not one “beginner box.” Higher cost per parameter. This is step-two precision, not the first purchase for a 10-gallon betta.
Watch-out: Easy to over-collect. Start with API master; add Salifert nitrate/phosphate if you are actually chasing algae.
Which kit for which job
| Job | Buy |
|---|---|
| New tank / fishless cycle | API Master, or API Ammonia if money is tight |
| Weekly check, tank already at 0/0 ammonia/nitrite | Master kit or EasyStrips |
| Shrimp / cichlid / pH bounce | Add API GH & KH |
| Planted, chasing algae | Add Salifert nitrate or phosphate later |
A test kit does not clean water. Your filter does. If readings say the cycle is done and you are shopping hardware next, use the filter-cartridge guide already on this site — not a second test-kit SKU.
FAQ
Are strips “wrong”?
They are coarse. Fine for “is nitrate roughly low” on a stable tank. Bad for “is there any ammonia” in week two of a cycle.
What numbers am I aiming at?
For a cycled freshwater community tank, the usual published target is 0 ammonia, 0 nitrite, nitrate kept modest with water changes, pH stable rather than perfect. Confirm with your species. The cycling article is the timeline; this page is the tool.
Can I skip testing if I do water changes?
You can get lucky. You cannot see ammonia. Test through the cycle and after any death, overfeed, or medication.
Sources
- API Freshwater Master Test Kit — manufacturer parameter list / published test count
- Cycling timeline on this site: /articles/how-long-to-cycle-a-fish-tank/
Last reviewed: August 2026. We will add a kit only when it is a real, current SKU.
