How To Raise GH And KH In Shrimp Tank?

How To Raise GH And KH In Shrimp Tank

Very often beginner shrimp keepers ask the question of why their shrimps are suddenly dying off or not thriving like before. From my experience, I will share with you the connection of GH and KH of your water and the well-being of your shrimp colony and how to raise these parameters to maintain a lively shrimp tank.

To raise the GH of your tank water you can use Shrimp mineral supplements, Equilibrium, GH booster, wonder shells, crushed coral, aragonite, etc. Alkaline buffer, aragonite sand, dolomite rock, and limestone are good for boosting up your KH.

You who have just started keeping shrimps must know about GH and KH first because these two factors have a lot to do with your shrimps, with their survival, development, temperament, breeding, and much more.

In this article, I’ll try to clear all those questions that came to my mind about GH and KH so that without any trial and error you can keep your shrimp colony happy forever!

multiple colored shrimps all grazing and having fun
Owner: Ricky Sales
Table of contents

What Is GH?

The overall amounts of salts (especially calcium and magnesium salts) or multivalent cations (calcium, magnesium, iron, etc.) in your water.

What Is KH?

The total amount of base-carbonates, bicarbonates, phosphates, hydroxides, etc.) in the water that neutralizes the acids to counter a sudden change of pH.

Are GH And KH Interrelated?

GH and KH are interrelated. Because GH refers to the sum of temporary hardness (which is the carbonate hardness or KH) and permanent hardness (non-carbonated hardness) of the water.

KH is called Temporary hardness because Ca and Mg carbonates precipitate as minerals if you boil the water.

But when Ca and Mg are associated with sulfates, chlorides, or nitrates they do not get changed even when they are heated that is why they are called permanent non-carbonic hardness (NCH). You can increase it by adding calcium or magnesium sulfate to your tank water.


GH= KH+ NCH+ PsH (where PsH stands for pseudo hardness caused by the carbonates by the monovalent cations-K, Na, Ammonium)

Can GH Be Raised Without Raising The KH And Vice-Versa?

Well, this question can be raised naturally.

From the above equation, you can see that you can increase the GH in your shrimp tank by simply increasing the temporary hardness (i.e. KH) or permanent hardness or both of them.

While Ca or Mg carbonates raise both GH and KH of water, K or Na carbonates will raise the KH of your water only because the GH of your water is concerned with only the amount of Ca and Mg salts.

So, you can raise your water’s KH easily by adding a significant amount of KHCOor NaHCO3 keeping the GH the same.

Again, if you add Ca(SO4)2 or MgSO4 it would only raise the GH as KH is concerned only with the changing of HCO 3 or H(CO3) 2 in the water.

So, you can raise only the GH without affecting the KH and vice versa when you need to do so.

gorgeous blue white shrimp
Owner: Kaz Brown

How To Raise GH In A Shrimp Tank?  

So, if your tank contains soft water but your pet shrimps demand hard water, these are some ways you can raise the GH to keep them happy.

1. Shrimp Mineral Supplement

Shrimp mineral supplement will provide all the minerals that your shrimps do not get from the soft water. It can re-mineralize RO-water, rainwater, and desalinated water-raising both the GH and KH keeping the GH double the KH.

If your pet shrimps are from neutral pH water, they also get acclimated to this water.

You will get hundreds of shrimp mineral supplements on the market that will re-vitalize your shrimp colony and give you a lively shrimp tank.

See also  How To Change TDS In A Shrimp Tank?

2. Seachem Equilibrium

This equilibrium is very popular among the shrimp keepers that will raise your GH which contains calcium sulfate and magnesium sulfate. Use it when you want to keep the KH and pH stable. You need to use it whenever you change your tank water.

3. GH Booster

You can also use a GH booster which will add calcium and magnesium sulfates to your water when you use soft water or RO water in your shrimp tank. GH Booster contains Magnesium Sulfate, Potassium Sulfate, and Calcium Sulfate in a 1:3:3 ratio.

4. Crushed Coral

Crushed coral mixed with the substrate or simply kept in a media bag in your shrimp tank slowly releases calcium and carbonate into your water. So, along with raising the GH, crushed coral will raise the KH of your shrimp tank.

So, if you want to only raise your GH, it is not for you. Again, crushed coral causes a sudden rise in the pH. As there is no instruction, you have to depend on guessing how many pieces you may need for your water.

5. Wonder Shells

If you want to raise the GH without impacting the KH and pH, then wonder shells can be a good option. They are completely natural and can dissolve in the water slowly and release magnesium and calcium into your shrimp tank.

They compensate for harmful acids that are created in the shrimp tank from organic decomposition if you keep them in a place in your tank where the water flow is low. Besides, they help to condition your water removing chlorine and chloramine.

Try a few of the shells at a time to get the optimum GH.

6. Cuttlebone

A safe way to raise your GH without causing overdosing. As the cuttlebone takes time to dissolve, it does not have the risk of overdosing.

7.  Aragonite

An available ingredient that comes as rocks or sand abounds with calcium carbonate. It will raise both the GH and KH of your shrimp tank and also add charm to your shrimp tank.

two bamboo shrimps
Owner: Sarah Louise Kennedy

Why Is GH So Important In Your Shrimp Tank? 

GH or the amount of Calcium and magnesium is essential for your shrimp tank as these two elements are necessary for the forming, digestion, and health of the breeding of your shrimp.

1. Molting:

Molting is a sign that your shrimp are thriving in good health. Calcium Carbonate plays an essential role as one of three main components in the molting cycle of your shrimps.

The new delicate shells of the newborn shrimps are developed and hardened when your shrimps absorb calcium carbonate from the water. The shell of a mature shrimp consists of of30-50% of Calcium Carbonates according to the studies.

So, if the total amount of calcium carbonate is low in your tank water, the shell development of your shrimps will be at stake.

2. Bodily Functions

The proper heart, muscle, and nerve function and digestion of your shrimps are also concerned with the concentration of Calcium in your tank water. Calcium and magnesium salts and cations of the water conduct electricity that is essential for these functions.

3. Osmoregulation

Osmoregulation is a natural process where your shrimps balance the salts and water inside their body with the salts and water of the tank.

So, it is necessary that your tank water contains the proper amount of salts (GH) because any imbalance of it can cause stress to your fish or even death.

Calcium and magnesium salts impact food digestion and levels of stress by controlling the osmoregulation process in your shrimp tank. It reduces stress in your shrimps and maintains their good health.

4. Improve Immune System

Calcium carbonate also controls the oxygen level and the toxicity of ammonia in your shrimp tank. Developing the immune system helps to fight toxins, infections, and diseases in the shrimp body to improve their overall health.

5. Breeding

GH is an effective factor in the breeding of your shrimps. If your shrimp tank does not have the optimal GH, your shrimp can lose eggs or stop breeding.

Although Magnesium does not impact your shrimp directly, do not dare to exclude it from the essentials!

It will help your shrimps to absorb Calcium Carbonates from the water so if you do not use Magnesium, the shrimps will face the deficiency of calcium carbonates and eventually die.

There should be 3 parts of Calcium and 1 part of Magnesium in the GH of your tank water.

This hard water will be enough to provide your shrimps with the amount of calcium and magnesium they need for their healthy life and breeding.

Different Shrimps & Their Ideal Water Parameters

different shrimps' ideal water parameters infographic

Want to get a printable version of this infographic? Click here! [If you want to use this infographic on your website, please link back to this post as the source!]

When Do You Have To Raise Your GH?

  • If your tank has very soft water
  • If you have a species of shrimp that thrives only in hard water

Check this table to know the level of GH your shrimps will love!

Different Shrimp Species And Their Required GH

SpeciesOptimal GH (ppm)GH Limits (ppm)
Bamboo shrimp6 – 81 – 15
Caridina cf. Babaulti6 – 84 – 14
Snowball shrimp6 – 84 – 14
Crystal red shrimp4 – 63 – 7
Ghost shrimp5 – 83 – 15
Amano shrimp7 – 85 – 15
Cherry Shrimp6 – 84 – 14
Cardinal shrimp

6 – 84 – 12
Blue tiger shrimp6 – 84 – 10
Blue bolt shrimp3 – 63 – 8
Vampire shrimp6 – 64 – 20


See also  How To Cycle A Shrimp Tank?

Can GH Change Without The Changing Of Water?

GH can get lower even without changing tank water as your shrimps use the minerals from the waters for different biological processes. GH can be higher than the optimal limit only when the water evaporates from your tank.

cherry shrimp hiding and grazing on tube hideouts
Owner: Sarah Louise Kennedy

How Often Should You Test The GH Of Your Tank?

Normally, you need not test your GH regularly if your water source has a moderate hardness. If your pet shrimps are very sensitive you should do the test every time you change your tank water.

Now, let’s dive into the KH of your water!

How To Raise KH In a Shrimp Tank?

Now, if you have a lower KH level than the optimal KH of your pet shrimps these are some ways you can raise the KH of your shrimp tank safely.

1. Water Change

Changing your tank water can be a way to raise KH if you have enough KH in your water.

You can restore the KH using Tap water if your KH is a little lower than optimal because you do not normally change the whole shrimp tank which eventually raises the nitrates from the decomposing organics on the bottom of your tank and hampers the molting cycle of your shrimps.

2. Crushed Coral

As I have mentioned earlier, Crushed coral is abundant with mostly calcium carbonate so it will raise your KH high easily.

3. Alkaline Buffers

Alkaline buffers raise KH safely and keep its level stable in your shrimp tank. They are available on the market.

3. Dolomite Rock (CaMg(CO3)2)

Another natural solution for raising KH contains a high percentage of mineral CaMg(CO3)2 that will provide calcium and magnesium to the water raising the GH while the carbonate will raise the KH. It is available in different colors on the market that will add beauty to your shrimp tank.

5. Aragonite Sand

It will be both a substrate for your shrimp tank and a good KH booster providing calcium and carbonate to the tank water.

6. Baking Soda (Sodium Bi-Carbonate)

Now, the most available ingredient from your kitchen. It can be a little tricky because you have to guess and try how much you will give in your water.

As it has no calcium or magnesium it will not raise the GH, only change the KH and pH.

7. Limestone (CaCO3)

Limestone will raise your KH. It can also change your pH very high. So, do not add overdoses or it will cause pH shock to your shrimps, and scatter it evenly in your tank.

Why Do You Need To Raise The KH?

The nitrates caused by defecation are acidic in nature which can cause a sudden drop in pH level.

We cannot get rid of these nitrates permanently. When you change the water, they eventually will go. But naturally, they will be back again.

That is why your tank water should have a higher KH so that it has the capability to neutralize more acids to balance the pH level. Thus, KH will act as a guard before the pH level of your water and accept and neutralize all the attacks from the acidic nitrates.

Does KH Get Low Without Changing Tank Water?

Carbonate hardness is consumed by the harmful nitric acid created from biological waste, respiration of shrimp, etc. As these processes go on, the KH level gets low gradually.

Why pH Consistency Is Crucial In A Shrimp Tank?

Sudden drops or rises in pH can cause shock to the shrimps. They can even die if they cannot get acclimated to the sudden change. That is why you should maintain pH consistency in your tank water.

How Will You Understand The Sudden Fall Of pH In Your Shrimp Tank?

Your fish will show some signs of stress when any sudden changes in pH occur. If you notice agitated swimming, inertia, fast breathing, or such unusual behaviors in your shrimp colony, test the pH of your water and take the necessary steps to keep it balanced.

crystal red shrimp with hideout decor
Owner: Kaz Brown

Can’t I Keep My Tank’s KH Very High?

This question may peep through your mind as you have seen how KH fights with the nitrates and keeps your water’s pH stable. So, why do many people keep their KH low? Well, there is a good reason behind it.

While many shrimp species like alkaline water or hard water, there are some species that love to live in acidic or soft water. So, the optimal KH and pH for these species are very low.

Here is a list of some shrimp species and their optimal KH for your convenience.

Different Shrimp Species And Their Optimal KH

SpeciesOptimal KH (ppm)KH Limit (ppm)
Bamboo shrimp2 – 61 – 11
Caridina cf. Babaulti3 – 80 – 12
Snowball shrimp2 – 41 – 8
Crystal red shrimp0 – 10 – 4
Ghost shrimp5 – 83 – 12
Amano shrimp2 – 41 – 8
Cherry shrimp2 – 41 – 8
Cardinal shrimp

4 – 83 – 10
Blue tiger shrimp2 – 41 – 8
Blue bolt shrimp0 – 20 – 4
Vampire shrimp2 – 15


How Will You Test The GH And KH Of Your Water?

To make sure when you have to raise these parameters you have to do a test of your tank water.

See also  19 Easiest & Hardiest Shrimps To Keep For Beginners

With the API Test Kit for GH and KH or any other test liquid test kit, you can check the GH and KH regularly.

How To Lower GH And KH In Shrimp Tank?

GH (General Hardness) and KH (Carbonate Hardness) are measures of the mineral content in aquarium water. High GH and KH can be harmful to some species of shrimp, as they prefer softer, more acidic water. Here are several methods to lower GH and KH in a shrimp tank:

1. Use RO/DI Water:

Reverse Osmosis/Deionized (RO/DI) water is purified water with most of the minerals removed. Mixing RO/DI water with tap water or using it exclusively can help lower GH and KH.

Reverse Osmosis Water Purification Process
Reverse Osmosis Water Purification Process

2. Use Soft Water:

If available, use naturally soft water which has a lower mineral content.

3. Use Peat Moss:

Adding peat moss to your filter or substrate can release tannins that soften the water and lower KH and GH. However, it can also lower pH and color the water.

4. Use Commercial Products:

There are commercial water conditioners and additives available that can lower GH and KH. Follow the manufacturer’s instructions carefully.

5. Use Driftwood:

Like peat moss, driftwood releases tannins that can soften water. It can also lower pH.

6. Use Catappa Leaves:

Indian Almond Leaves or Catappa leaves can also release tannins that soften water and lower pH.

7. Use Rainwater:

Collecting and using rainwater can be an option as it is usually soft, but it should be used with caution as it can contain pollutants.

8. Remove Carbonate Hardness:

Boiling or aerating water can help to remove temporary hardness (carbonate hardness) by precipitating calcium carbonate out of the water.

Is crushed coral good for a shrimp tank?

Crushed coral can be used in aquariums to increase the water’s general hardness (GH), carbonate hardness (KH), and pH. This can be beneficial for certain species of shrimp that thrive in harder, more alkaline water, such as Amano shrimp or certain types of Sulawesi shrimp.

However, many popular freshwater shrimp species, like the Red Cherry Shrimp, prefer softer, more acidic water conditions. In such cases, using crushed coral could create an environment that is less than ideal for these shrimp, potentially leading to health issues.

Considerations Before Adding Crushed Coral To Shrimp Tankl

  1. Shrimp Species: Research the specific needs of your shrimp species to determine whether they prefer hard or soft water, and adjust your tank conditions accordingly.
  2. Water Testing: Regularly test your water’s pH, GH, and KH to monitor the effects of the crushed coral and ensure the water parameters are within the suitable range for your shrimp.
  3. Amount of Crushed Coral: If you decide to use crushed coral, start with a small amount and monitor the water parameters closely, adjusting the amount as needed to reach the desired levels.
  4. Placement: Place crushed coral in a media bag within the filter or as a substrate layer, depending on your preference and the specific needs of your tank.

How to raise GH without raising KH?

Raising General Hardness (GH) without affecting Carbonate Hardness (KH) can be achieved by adding minerals that primarily contain calcium and magnesium, without adding carbonates or bicarbonates. Here are a few methods to raise GH without impacting KH:

Use a GH Booster:

Commercial GH boosters are available that are specifically designed to raise GH without affecting KH. These typically contain calcium and magnesium salts. Follow the manufacturer’s instructions for dosing.

Add Calcium Chloride and Magnesium Sulfate:

You can add calcium chloride and magnesium sulfate (Epsom salt) to increase the calcium and magnesium levels in the water, thus raising GH.

A common ratio is 3 parts calcium chloride to 1 part magnesium sulfate, but this can be adjusted based on the specific needs of your tank.

Dissolve the salts in water before adding them to the tank to avoid harming the inhabitants.

Use Seachem Equilibrium:

Seachem Equilibrium is a product designed to raise GH without affecting KH. It contains calcium, magnesium, and other essential minerals. Follow the manufacturer’s instructions for dosing.

Use Mineral-Rich Decor:

Adding mineral-rich decor like Wonder Shells can also help in increasing the GH without affecting the KH.

Nutrition Profile of Cuttlebone (Derived From Cuttlefish)

How to add calcium to the aquarium for shrimp?

Adding calcium to an aquarium is crucial for shrimp as it aids in the development of their exoskeletons. Here are several ways to add calcium to your shrimp aquarium:

1. Calcium Supplements:

Commercial Calcium Supplements: There are many commercial products available that are designed to add calcium to aquariums. Follow the manufacturer’s instructions for dosing.

Calcium Carbonate: This is a common form of calcium supplement that can be added directly to the aquarium. It may also affect pH and hardness, so monitor water parameters closely.

2. Cuttlebone:

A piece of cuttlebone can be added to the aquarium. Shrimp will graze on it, and it will slowly dissolve in the water, releasing calcium. It can also increase the pH slightly, so monitor the water parameters.

3. Eggshells or Crushed Coral:

Cleaned eggshells or crushed coral can be placed in the filter or substrate. They will slowly dissolve, releasing calcium into the water. They can also affect pH and hardness.

4. Calcium-Rich Foods:

Feed shrimp calcium-rich foods like spinach, kale, or commercial shrimp foods that are high in calcium. This will help shrimp ingest the calcium they need.

5. Mineral Blocks or Stones:

Mineral blocks or stones, like mineral-rich montmorillonite clay or Wonder Shells, can be added to the aquarium. They slowly dissolve, releasing calcium and other minerals.

6. Water Changes with Hard Water:

If your tap water is hard (rich in calcium and magnesium), regular water changes can help maintain adequate calcium levels.


So, maintaining the optimal GH and KH in your tank water is a must for the proper growth and breeding of your shrimps and for giving them a stable life with a constant pH level. Because men can keep pace with the ups and downs in their life but your shrimps can not!

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Muntaseer Rahman

About Author

Hello, I’m Muntaseer Rahman, the owner of I’m passionate about aquarium pets like shrimps, snails, crabs, and crayfish. I’ve created this website to share my expertise and help you provide better care for these amazing pets.


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