The water parameters I recommend
| Measure | My advice and how to use it |
|---|---|
| Temperature | I consider 22–24°C ideal, although I’ve also kept colonies around 20°C. Keep your tank’s temperature steady. |
| pH | 6.5–8.5 is a broad tolerated range. Compare with the supplier’s conditions; avoid chasing a different value unnecessarily. |
| GH | I recommend at least about 6 dGH as a starting reference. That doesn’t mean higher hardness is always better. |
| KH | I recommend 4–8 dKH, considered alongside your pH and source water. |
| Ammonia and nitrite | Undetectable on a suitable aquarium test. |
| Nitrate | Check your source water as well as the tank, and prevent sustained accumulation. Don’t treat another colony’s tolerance as a safe limit for yours. |
Use these figures as a starting point, rather than a guarantee that everything is fine. I also recommend asking your breeder what conditions their shrimp are used to. If a test gives an unexpected result, investigate it before adding treatments.
GH and KH do different jobs
General hardness, GH, describes the water’s calcium and magnesium content. Carbonate hardness, KH, is used by aquarium keepers to assess buffering associated with resistance to pH change. A tank can have a reasonable reading for one and an unsuitable reading for the other.
Hardness expressed in degrees can be converted to ppm as calcium carbonate: 1 degree is approximately 17.9 ppm. This conversion does not apply to a nitrate reading. Check the units on your kit before comparing two results.
TDS is a trend, not a complete water test
A typical aquarium TDS meter estimates dissolved solids from electrical conductivity. It cannot tell you how much of that reading is useful calcium or magnesium, nor replace ammonia and nitrite tests. Two samples with the same displayed TDS can have different chemistry.
My advice is to use TDS to spot a change in your water source or mixing routine, alongside the tests that identify the substances you need to manage. Do not add minerals just to make the display match another keeper’s number.
Watch my video
I explain pH, GH, KH and TDS in this video. I also discuss Caridina, so use the Neocaridina guidance above for your cherry shrimp.
Loads from YouTube when you choose. Watch on YouTube
Keep replacement water consistent
Condition tap water for chlorine or chloramine as directed by the conditioner manufacturer. Check its hardness and nitrate level as well as the aquarium’s. If using reverse-osmosis water, prepare it with an appropriate remineraliser before a water change and verify the resulting GH and KH.
Match temperature reasonably closely and add replacement water gently. Evaporation removes water but leaves most dissolved minerals behind, so topping up and changing water are different tasks. Repeatedly topping up with hard water can progressively raise mineral concentrations.
When a test looks wrong
Repeat the test, check its expiry and instructions, and record the result. Detectable ammonia or nitrite calls for prompt investigation of filtration, recent additions and waste. Use the troubleshooting guide if animals are distressed. For a healthy colony with an unexpected hardness or pH result, identify the cause and plan gradual corrections rather than repeatedly dosing the tank.