How to Use Salt Tablets for a Water Softener: A Guide to Tablet Salts

Water softener salt is typically made from food-grade salt that is refined to create tablet salts, block salts, or granular salts. Tablet salts are ideal for preventing limescale buildup, as they dissolve easily and reduce the need for frequent tank cleaning. In fact, many consider salt tablets to be the standard for water softeners.

In this guide, we will discuss what sets them apart from other forms of salt, as well as how to get the best value and performance from your tablet salts. 

What are the types of water softener salt?

First things first: how do tablets compare to the other types of water softener salts available to you? 

Grade AA tablet salts are built to dissolve evenly, reducing the residue that would otherwise be left in your water softener. All Culligan Harvey water softeners are supported by grade AA salts, ensuring effective ion exchange and reduced maintenance throughout the year.  

Note: Always check the guidance for your water softener to be sure you’re using the correct type of salt. Using the wrong variety may damage your softener.

Tablet salts

Tablet salts are small pellets of high-quality salt, easy to unload into the brine tank of your water softener. It is also considered to be high-purity compared to other types of water softener salts, but this can vary. 

Table salts are compatible with most domestic or commercial water softener systems, and are the most common form of water softener salt due to their ease of use and efficient dissolution rate.

Block salts

Block salts can be more expensive than tablet salts, but generally are easier to place in your brine tank, as you are dealing with one large block of salt instead of many small pellets. 

This type of salt also lasts longer between refills than tablet salts, as it takes longer to dissolve. Be careful to use a high-quality block salt with no caking agents or additional minerals- AA-grade salt should be 99% pure, meaning you’ll get the best value for your money with no damage to your system.

Granular salts

Granular salts are typically on the more expensive side of the scale, and resemble table salt to an extent, in that these are small granules often no larger than 2-6 mm. They are mostly used in older water softeners, swimming pools, and dishwashers. 

This type of salt is designed for maximum performance, dissolving easily whether it’s placed into a domestic or industrial softener. 

How to use salt tablets for water softener

Using tablet salts in your water softener is fairly simple:

1. Identify the brine tank – This is the compartment where the salt is stored and dissolved to create the brine needed to soften your water. 
2. Add the salt to the recommended level – In general, you’ll need to fill about two-thirds of your tank. The amount of salt you require depends on the amount of water your household uses, but be sure to keep your softener well-stocked, checking salt levels at least once a month. You can even monitor your salt levels remotely with the MyHarvey App.
3. Run your softener as needed – Keep an eye on the salt levels. Many water softeners automatically ‘regenerate’ when needed, a process that requires salt to maintain your system’s performance. 

How to use block salt in your water softener

As with tablet salts, you’ll need to understand where your brine tank is and how to load it – luckily, this is fairly easy with block salts. 

Note: Block salt can also be hazardous to your water softener if it is not compatible with your system, so be sure to check before you start. To use salt blocks, you should have a ‘post-fill’ water softener that refills the brine tank with water at the end of each regeneration cycle. 

1. Place your water softener salt blocks in the brine tank. Depending on the size of your system and the size of the blocks, you may need to stack a few on top of each other. In general, having the tank one-quarter to one-half full of block salt should be enough.
2. Ensure the blocks are submerged in water – this will enable them to dissolve easily. Leaving some space in your tank will also prevent ‘bridging’, where salt hardens and causes issues for your machine. 
3. You’ll need to replace block salt less often than granular or tablet salt, but it’s still worth monitoring the salt levels in your machine and topping up when necessary to keep everything running smoothly. 

How to use granular salt in your water softener

Granular salt is best suited for older models of softener, as well as general dishwasher use. 

1. As with block salt, it is best to fill the brine tank until it is roughly one-quarter to one-half full, to ensure all salt dissolves properly. Simply pour the salt into the brine tank as recommended. 
2. Regularly check and clean your brine tank – Granular salt may be more likely to ‘clump’ together on the sides of your water softener system, eventually forming a ‘sludge’ as the salt dissolves. Use a high-quality, AA-grade salt to minimise the likelihood of such buildup. 
3. Do not use granular salt in your water softener if you have previously used tablet or block salt, as this can result in significant performance problems and ultimately ruin your water softener. 

Where can I buy tablet salt for my water softener?

Most water softener brands sell complimentary salts. However, there are several things you should consider to ensure the salt you select will provide the best value for your machine without causing any damage.

• Look for high-quality, grade A salt with +99% purity- this will reduce the risk of any residue or ‘sludge’ building up in your water softener. 
• High-quality salt will also dissolve more easily in your softener, reducing the risk of issues like clogs or bridging that could otherwise lead to costly repairs. 
• Check the manufacturer’s recommendations to ensure you use the right type of salt for your machine. 
• Don’t be turned away by a high price tag- more expensive salts can actually save you money in the long run, as you’ll need to replace these less often and your water softener will run more efficiently overall. 
• Avoid salts with unnecessary additives – pure sodium chloride is suitable for most machines. 

Low-quality salt can void your water softener warranty, so be sure to make a sensible choice when selecting the right salt for your system. 

We offer grade AA water softener salt without unnecessary anti-caking agents or additives, with next working day delivery available. 

How do I know how much salt I’ll need?

When buying water softener salt, it can be tricky to understand how much you’ll need to enjoy softened water with no complications. Here are a few things to keep in mind:

Understand the make and model of the water softener you have

Salt usage varies significantly between single-cylinder, double-cylinder machines, and also the size of your water softener system. Newer models typically run more efficiently and require less salt. 

Water softeners with larger brine tanks, of course, hold more salt. While this can mean you don’t need to refill your tank as frequently, it can also mean your system requires more salt per regeneration cycle. 

Understand how much water you use

A single person uses approximately 149 litres of water per day in the UK, while a four-person household uses upwards of 400 litres. 

The more water you use, the more your water softener will run, and the more salt you’ll need to ensure the system can regenerate properly. 

Understand the water hardness level where you live

The harder the water where you live, the more salt you will need to soften it. 

Consult the directions relevant to your water softener system for further guidance. In general, allowing salt levels to regularly drop below the water line, while also regularly adding more salt, will keep your water softener functioning properly. 

Meet the mini-curve: water softener salt made better

Harvey Mini Curve Salt is the unspoken fourth type of salt, compatible with the HarveyArc water softener. It is made with quality grade A salt and carries all the benefits of block salts:

• It is compact and light, making it easy to transport
• It is larger than tablet salts, making it last longer without sacrificing efficiency

Mini Curve Salt is perfect for use with the Smart HarveyArc, shaped to fit perfectly into the system so you never wonder if you’re using enough salt – you know you are. 

Learn more about our water softener salts here.

Water softener salt FAQ

Can water softener salt be unhealthy?

For most people, water softener salt will not impact your wellbeing in any way. However, for people on an extremely low-sodium diet prescribed by a medical professional, it may be recommended to avoid drinking softened water.

Is water softener salt safe for pets?

Some people find themselves concerned about the increase in sodium levels in softened water, especially when furry friends get involved. However, this does not present any risk in healthy pets. In dogs with cardiovascular issues, this may be a concern, but the majority of pets will not be affected. 

How long does water softener salt last?

On average, most new water softener models need new salt every 6-8 weeks. However, this can vary according to your household water usage, water hardness in your area, and the type of salt you use. 

What can I use water softener salt for?

While water softener salt can be considered ‘food grade’, it is not advised to eat it. Instead, use it to soften water, melt ice or snow outside your home, kill weeds, or deter slugs and snails.