When your pool water turns a brown, reddish or blackish colour, it is likely there is a high level of metal deposits in your water. These can appear for a number of reasons but mainly if the pool has been filled using water that contains a high level of some of these metal elements. 

It is so important to treat this issue and remove these metal deposits before they permanently stain your pool surfaces and surrounds.

Solutions:

> Check and readjust the pH to between 7.0 and 7.4 with HTH pH PLUS or HTH pH MINUS

> Use a metal removing agent such as HTH METALSTOP

> If necessary, apply a liquid flocculant such as HTH RAPIDFLOC, with the filter switched off for 12 hours then vacuum the deposits by sending them to the waste without going through the filter

> If needed, use mains water to top up your pool

Do you have trouble seeing the bottom of the pool? There are several reasons why your water can turn a milky or cloudy colour.

Your pH may be imbalanced

There is not enough disinfectant (bromine, chlorine etc.)

Your filtration time is not suitable

Your water may be over-stabilised

If your levels are reading correctly, it may be that the suspended particles in your water are too small to be filtered out.

Solutions:

> Your pH is not right:

Readjust the pH to between 7.0 and 7.4 with HTH pH PLUS or HTH pH MINUS

> If the quantity of disinfectant (chlorine, bromine, etc.) in the water is insufficient:

Apply a shock treatment with HTH SHOCK Powder

Use HTH RAPIDFLOC, a liquid flocculant for sand filters, which will clarify the water by precipitating impurities to the bottom of the pool. To be used with the filter switched off. 

Then backwash the filter several times and let it run continuously for 24 to 48hrs. This action will significantly improve the filtration quality and thus, help maintain crystal clear water

> If the filtration time is not suitable:

Adapt the filtration time to the water temperature according to the following calculation:
Water temperature / 2 + 1 hour.

Preferably run your filtration during the day rather than at night

> In the event of over-stabilised water:

Check the stabiliser content; if it exceeds 80 ppm, you need to partially or fully empty out the pool:
From 80 to 120 ppm: ½ the pool
Above 120 ppm: ¾ of the pool

Use HTH STICK (non-stabilised chlorine) as a regular treatment to avoid over-stabilisation.

To prevent cloudy water and improve filtration fineness, HTH REGULARFLOC improves the day-today filter fineness of pools with sand filter.

You may have an over-stabilisation problem. This happens when your pool has been routinely treated (with the best of intentions) maybe with a chlorine tablet per week, a shock treatment once a fortnight and a little clarifier here and there. Everything is all good and well, until the water goes green and algae appears! This happens when stabilised chlorine is used regularly and the stabiliser (cyanuric acid) builds up in the water. 

When there is excessive stabiliser in the water the disinfectant action of the chlorine molecules is slowed down and can be stopped entirely. Even adding more chlorine will not fix this. Micro-organisms will began to grow and the water will turn. Viruses and fungi will no be being killed - certainly not water you want to be swimming in!

Solution:

Unfortunately, the only solution is to remove the excess quantity of stabiliser by emptying out a large amount of the pool water (sometimes all the water) and adding fresh water. This solution is a hassle in the middle of the season and can be costly. 

It is then preferable to use non-stabilised chlorine HTH (red range) as a preventive solution in order to avoid the over-stabilisation of your water.

Your pool can be green for a few reasons; phosphates and algae, imbalanced pH, not enough chlorine or over-stabilisation.Slippery and unsightly, see our solutions below:

Solutions:

> Brush the pool walls and skimmer basket 

> Adjust the pH to between 7.0 and 7.4 with HTH ​pH PLUS or HTH pH MINUS

> Apply a shock chlorination treatment with HTH SHOCK Powder

> Wash and rinse the filter 

> Let the filtration run during 24hrs

> Place one or more HTH REGULARFLOC flocculant cartridges in the skimmer

> Use a concentrated anti-algae product: 

> To protect your pool and fight against the proliferation of common algae, use HTH SUPERKLERAL, a non-foaming anti-algae product especially adapted to turbulent water (powerful filtration, counter-current system, jets, etc.)

> Certain types of algae found in swimming pools, such as black or pink algae, are especially resistant, even to chlorine. In this case, use HTH BLACKAL SHOCK, an effective treatment thanks to its copper-based formula.

> Check the stabiliser content; if it exceeds 80 ppm, you need to partially or fully empty out the pool:
- From 80 to 120 ppm: ½ the pool
- Above 120 ppm: ¾ of the pool

> Use HTH ADVANCED (non-stabilised chlorine) as a regular treatment to avoid over-stabilisation.

> Phosphates are the main source of nutrients for algae. Regularly check the phosphates level in the water and treat the water if needed with HTH ANTI-PHOSPHATES

Pool water filtration is the first step in treating your pool. If your filter isn’t in prime condition then neither is your water. 

Whatever filter you choose, the operating principle of a filtration system is similar: the pool pump drains impurities into the filtration system and removes dirt from the water before returning the water back into the pool or spa through the outlet nozzles. 

The filter will naturally become dirty during its operation. Some filters are equipped with a manometer which indicates their internal pressure. If this manometer indicates an unusually high pressure: the filter is likely dirty.

Keep an eye on your filter system as part of your weekly checks.

Solutions:

> Backwash the filter

> If the high pressure persists, descale the filter with HTH FILTERWASH. This product cleans and descales sand filters, diatomaceous earth filters and salt electrolytic cells

Have you been enjoying your pool or spa all summer long but suddenly your eyes are red and itchy and there's an overwhelming smell of chlorine coming from your pool?

Every swimmer that uses the pool brings their organic contaminants with them. The chlorine in your pool or spa works to keep these at bay as free chlorine (FAC), however, the chlorine molecules that combine with the contaminants become ‘used up’, this combined chlorine is a much weaker disinfectant, known as chloramine. Chloramine has a much stronger smell than chlorine and contributes to skin, eye and respiratory irritation. Therefore, you want to keep your FAC levels in check. 

Ironically, the best solution is to shock your pool with chlorine to remove the chlorine smell. If total chlorine is higher than free chlorine, there are contaminants in the pool. You will need to subtract the free chlorine measurement from the total chlorine measurement to calculate the amount of combined chlorine (total – free = combined). If combined chlorine is higher than 0.5 ppm you should shock the pool. Use our specialised test strips for regular checking.

Solutions: 

> Re-adjust the pH to between 7.0 and 7.4 with HTH pH PLUS or HTH pH MINUS 

> Apply a shock chlorination treatment with HTH SHOCK Powder 

> Keep the chlorine content at 2 mg/l by regularly adding chlorine tabs or sticks to be placed in the skimmer every week

Is your chlorine test showing zero during analysis despite you regularly adding disinfectant? There are two possible reasons for this. Either the content is so high that it is unreadable to the test or the chlorine content is so low it cannot be detected.

In this situation we would recommend asking a specialised pool engineer to advise you which it may be. 

Solutions:

> If you have an unusually low chlorine reading, ask your engineer for a full analysis.

> Re-adjust the pH to between 7.0 and 7.4 with HTH pH PLUS or HTH pH MINUS

> If not enough chlorine: apply a shock treatment with HTH SHOCK Powder

> If too much chlorine: neutralise the excess chlorine or bromine with HTH NEUTRALISATOR

Is your pH unstable and difficult to stabilise? The optimum pH for pool water is between 7 and 7.4. The reason it cannot be stabilised is due to incorrect TA (total alkalinity). If your TA is too high it can create resistance to pH changes, and if your TA is too low the pH level in your pool can become erratic. The TA must be between 8° f and 14° f (80 mg/l and 140 mg/l). Once TA is back in balance your pH levels can be adjusted and safely maintained. 

Solutions:

> The TA is too high: add HTH pH MINUS
 

> The TA is too low: adjust the TA with HTH ALKANAL at the beginning of the season, then once a month. Adjust it gradually by 3° f intervals (30 mg/l )

There are a number of reasons why a pool liner will wrinkle, not only can temperature and poor installation be a cause but so can some chemical imbalances. If the pH is too low, this can cause irreversible wrinkles in the liner and gradually corrode the pool equipment. It is important to regularly check your pool water’s pH or install an automatic pH regulation system. Likewise, if your chlorine levels are consistently far too high then this can cause a wrinkled liner issue. 

High chlorine and low pH can be very corrosive, they literally strip the plasticiser from the vinyl, causing the liner to contract and pucker.

 Solutions:

> Increase the pH with HTH pH PLUS

> If the pH is unstable, check the TA level to avoid pH variations 

> Reduce high chlorine levels with HTH Neutralisator

Broadly speaking, phosphorus is a simple chemical compound, absolutely essential to life, and represents 2 to 4% of living matter. Phosphates are produced by the oxidation of phosphorus and are among the essential compounds for the survival of living organisms.

Pool water becomes polluted with phosphates, they are released by all living organisms, and are present in top-up water, rainwater, urine, plant waste, fertilisers and even in dust. Over time, phosphates gradually build up in the pool water, especially when it is not often topped up with fresh water. You may kill the algae with an algaecide but the algae just reappears. It is likely this is due to the high phosphate level in your water.

 Phosphates are the main source of nutrients for algae, they encourage their development, even in the presence of chlorine. Some of the phosphates are consumed by the algae, but the algae also release some when they die. 

 Solutions:

If there are phosphates in your pool, use HTH ANTI-PHOSPHATES. A durable and effective solution to eliminate phosphates from your pool water once and for all, and limit algae issues.

Are you finding it hard to maintain your chlorine levels? None of your chemicals will work as efficiently if your pH is not within the correct levels. Your chlorine may also be depleted too quickly if you have recently used too much chlorine reducer or if your pool is used by many bathers (and consequently, consumes more chlorine) or even in the event of  weather storms. 

Solutions:

 > Re-adjust the pH to between 7.0 and 7.4 with HTH pH MINUS
 or HTH pH PLUS

> Apply a shock chlorination treatment with HTH SHOCK Powder

Green algae: this algae is the easiest to recognise as it turns your water green. It has a slimy feel that makes the walls and bottom of your pool slippery.

To treat green algae: apply an HTH shock treatment then use the HTH ULTRAKLERAL product or HTH SUPER KLERAL. 

Black algae: you will see small black spots appear on the walls and floor of your swimming pool or in the grouts of tiled pools. This algae is very resistant, make sure to eliminate its root cause.

To treat black algae: brush the floor and walls of your pool, apply an HTH shock treatment and add the HTH BLACKAL SHOCK product.

Mustard algae : looks similar to pollen or yellow dust. This algae develops in the darker areas of a swimming pool.

To treat mustard algae: brush the floor and walls of your pool, apply an HTH shock treatment and add the HTH BLACKAL SHOCK product.

In order to avoid re-growth, analyse whether your pool may have too many phosphates or be over-stabilised and consult our other FAQ’s

If your grout in your pool starts to soften and you can see it flaking off you need to increase the hardness of your pool water. The soft grout is caused by soft water because it is deficient in calcium or magnesium ions. Therefore, it is naturally aggressive towards cement based materials and can leach calcium ions from cement. This weakens the structure of the cement resulting in a softening or erosion of the grout from between the tile joints. 

Solutions:

> Contact your pool specialist for a full water analysis 

> Use a Hardness Increasing product to raise the levels of calcium in your water.

Did you know equipment failure can be caused by water imbalances? If your water is very acidic, ie consistently at a low pH the water is deficient in mineral ions and will strip the deposits from the metal in your equipment. Not all equipment issues are electrical. 

Solutions:

> Test your water with our advanced test strips once a week.

> Keep your pH levels at an optimum level 7.0-7.4, use HTH pH PLUS if needed

> Increase the calcium in your soft water if necessary by using a hardness increasing product - contact a swimming pool engineer for a full analysis.

Are you loving opening and closing your pool with the flick of a switch but no so in love with the deposits building up on your slatted cover? Pools with high Total Hardness, hight pH or high Total Alkalinity are prone to developing scale and deposits around any fixtures and fittings and the slatted pool cover. The best way to deal with this is to prevent it in the first place. Keep your alkalinity and pH in the optimum ranges to avoid the issues. However, if you have developed this problem then a slatted cover cleaner or descaler will do the trick.

Solutions:

> Test your water with our advanced test strips once a week.

> Keep your pH levels at an optimum level 7.0-7.4, use HTH pH PLUS or MINUS if needed

> Increase the calcium in your soft water if necessary by using a hardness increasing product - contact a swimming pool engineer for a full analysis.

> Use a descaling cleaning product such as a slatted cover cleaner or our HTH BORKLER Gel