pH for Caridina and Neocaridina shrimp: ideal values and tips

The aquarium pH is one of the most important parameters to monitor when keeping Caridina or Neocaridina shrimp.

But looking for a "perfect pH" alone is a common mistake: for shrimp, water stability, GH, KH, conductivity, and temperature are just as important.

In this guide, we will look at what pH to aim for with the main aquarium shrimp, how to measure it, and above all, how to avoid sudden fluctuations.

What is aquarium pH?

The pH measures the acidic, neutral, or alkaline nature of water on a scale from 0 to 14:

• pH less than 7: acidic water
• pH equal to 7: neutral water
• pH greater than 7: alkaline or basic water

In a shrimp aquarium, the pH should never be considered in isolation. It is strongly linked, in particular, to KH, the substrate used, and water preparation.

Which pH for Caridina and Neocaridina shrimp?

These values are benchmarks, not absolute limits. A shrimp properly acclimated in stable water can sometimes be kept slightly outside these ranges.

Conversely, trying to quickly modify an aquarium just to hit a specific number can be much more problematic than a slightly different but stable pH.

Which pH for Caridina Crystal Red and Taiwan Bee?

Crystal type Caridina, Taiwan Bee, Blue Bolt, Panda, or King Kong are generally kept in very soft, slightly acidic water.

In this type of aquarium, you will frequently find:

• reverse osmosis water;
• remineralization adapted mainly to GH;
• a very low KH, or even close to zero;
• an active substrate used to buffer the water towards an acidic pH.

A pH roughly between 5.5 and 6.5 is therefore common in aquariums dedicated to Caridina Bee.

Which pH for Neocaridina?

Neocaridina davidi such as Red Cherry, Sakura, Blue Dream, Bloody Mary, or Yellow Neon generally tolerate more mineralized water.

A pH around 6.5 to 7.5 suits many populations, provided that other parameters are adapted and, above all, stable.

Neocaridina can be more tolerant than Caridina Bee, but that does not mean they should be subjected to significant parameter fluctuations.

Why is pH stability so important?

Shrimp live in constant contact with their environment. A rapid change in water composition requires significant physiological adaptation.

It is therefore preferable to have a pH slightly different from the theoretical value but stable rather than causing frequent, sharp variations to reach a specific number.

Variations can occur, in particular, after:

• a water change with very different water;
• a significant change in KH;
• exhaustion of an active substrate;
• the addition of calcareous materials;
• a significant change in CO₂ injection;
• poor preparation of remineralized water.

What is the role of KH in pH?

KH primarily represents the carbonate buffering capacity of the water. The higher the KH, the more the water generally resists pH fluctuations.

This is why Neocaridina aquariums often function with a measurable KH, whereas Caridina Bee aquariums on active substrate are frequently maintained with a very low KH.

In a Caridina aquarium using an active substrate, adding water highly loaded with carbonates can also gradually reduce the effectiveness of the substrate.

What is the difference between pH, GH, and KH?

These three parameters should not be confused:

• pH: indicates whether the water is acidic or alkaline;
• GH: primarily represents the concentration of calcium and magnesium;
• KH: represents part of the water's buffering capacity.

To properly keep shrimp, you must therefore look at all parameters, not just the pH.

How to measure the pH of a shrimp aquarium?

Several solutions exist:

• drop tests: simple and sufficient for many aquariums;
• electronic pH meter: interesting for more precise measurement, provided it is correctly calibrated;
• test strips: convenient for a quick indication but generally less precise.

For a specialized Caridina aquarium with very soft and acidic water, a correctly calibrated pH meter can be particularly convenient.

How to lower the pH for Caridina?

In an aquarium dedicated to Caridina Bee, the goal is generally not to pour in a product designed to artificially lower the pH.

The most common method relies instead on:

• remineralized reverse osmosis water;
• a very low KH;
• an active substrate adapted for shrimp;
• water changes performed with identically prepared water.

This combination allows for an environment that is much more stable than a succession of chemical corrections.

Do Catappa leaves actually lower the pH?

Catappa leaves release tannins and various organic acids. They can slightly influence the pH in very soft, weakly buffered water.

In water with a high KH, however, their effect on pH can be very limited.

Catappa should therefore not be considered a reliable method for adjusting the pH of an aquarium on its own.

To learn more, check out our complete guide to Catappa leaves in the aquarium .

Can you use tap water for shrimp?

This depends entirely on its composition.

Tap water that is sufficiently stable and adapted can perfectly suit some Neocaridina.

For Caridina Bee, tap water is often too mineralized or has a KH that is too high. Breeders then frequently use reverse osmosis water remineralized with adapted salts.

Does active substrate lower the pH?

Yes, an active substrate for shrimp can buffer water towards acidic values when used with adapted water that is low in carbonates.

Its effectiveness is not permanent, however. Over time, its buffering capacity may decrease.

A gradual rise in pH in a Caridina aquarium can therefore sometimes be a sign that the substrate is starting to lose its buffering power.

Why does the pH change between morning and evening?

The pH can naturally evolve during the day, notably because of CO₂ dissolved in the water.

At night, plants and organisms respire and produce CO₂. During the lighting period, plants consume some of this CO₂ through photosynthesis.

It is therefore better to compare measurements taken at similar times when you want to track pH evolution.

Should you try to quickly modify a "bad" pH?

No. Unless there is a specific situation, it is generally better to understand the cause of the problem before intervening.

If your pH does not match the species kept, check in particular:

• the KH;
• the GH;
• the conductivity;
• the composition of the water used for changes;
• the condition of the active substrate;
• the possible presence of stones or calcareous materials.

Modifying only the pH without understanding the rest of the water chemistry can create more instability.

Frequently asked questions about shrimp pH

Which pH for a Red Cherry?

A Neocaridina Red Cherry is generally kept around pH 6.5 to 7.5, with sufficiently mineralized and stable water.

Which pH for a Crystal Red?

Caridina Crystal Red are generally kept in soft, acidic water, often around pH 5.5 to 6.5.

Which pH for a Taiwan Bee?

Taiwan Bee are usually raised in conditions similar to Crystal, with very soft water, very low KH, and an active substrate.

Is a pH of 7 dangerous for Caridina?

This depends on the Caridina species. For selective Caridina Bee, a stable aquarium around more acidic values is generally preferred. However, you must avoid causing a sudden drop in pH just to reach a theoretical value.

What is most important: pH or conductivity?

Both provide different information. pH provides information about water acidity, while conductivity gives an indication of the total quantity of dissolved substances. They must be interpreted alongside GH, KH, and other parameters.

In summary: which pH for Caridina and Neocaridina?

• 🦐 Caridina Crystal and Taiwan Bee: generally around pH 5.5 to 6.5.
• 🦐 Neocaridina: generally around pH 6.5 to 7.5.
• 💧 The pH must always be interpreted with GH and KH.
• 📏 A stable value is better than constant corrections.
• 🌱 For Caridina Bee, an active substrate combined with remineralized reverse osmosis water is a common method.
• ⚠️ Avoid sudden changes in water chemistry.

Final words

There is no single ideal pH for all shrimp. The needs of a Neocaridina Red Cherry are different from those of a Caridina Taiwan Bee.

To succeed with your aquarium, aim above all to obtain parameters that are consistent with the species and, most importantly, stable over time.

To further your knowledge on keeping your shrimp, also check out our complete Caridina & Neocaridina guide .