Why is my spa water cloudy? If I’ve heard that question once, I’ve heard it a thousand times. It may be the number one spa water problem plaguing spa owners.
There is a lot of misinformation out there about cloudy spa water – such as, “Bromine will make your spa cloudy”, or “Metals in the water cause cloudy hot tub water”, or the constant sales pitch – that if you just had this super-special-magical spa water treatment, your spa water problems will disappear.
If your spa or hot tub water is cloudy, hazy, milky – turbid, as I sometimes call it, your problem will be one of these situations below, or a combination of more than one.
1. High Calcium Hardness or Total Alkalinity
Your spa water chemical balance may be to blame, and it’s the first place I would check. Take an accurate reading of your calcium hardness, alkalinity and pH levels. In areas where hard water is common, calcium can easily come out of solution and cloud the spa water. If your calcium hardness levels are greater than 300 ppm, use Calcium & Scale Control to tie-up minerals in solution, and keep them from making your spa water cloudy.
If your test for Total Alkalinity shows high levels, in excess of 150 ppm, excess carbonates can come out of solution, and make the spa cloudy. High TA levels will also make it hard to control your pH, or keep it in range. Use pH decreaser to lower TA to around 100 ppm. If your spa pH level is outside of the range of 7.2-7.6, adjust accordingly for easier control of cloudy water.
TDS, or total dissolved solids, is not usually a concern in spas and hot tubs – but, if you have not drained your spa in years, for whatever reason – you may have a very high level of dissolved solids in the water. When water reaches it’s saturation point, where it can absorb no more solids, frequent bouts of cloudy water are the result. Time to drain and refill the spa.
2. Low Spa Sanitizer Levels
Some people are sensitive to bromine or chlorine, and try to operate the spa with as little as possible. That may be OK, if you have other sanitizers working, such as an ozonator, or a mineral cartridge, and your water chemistry is balanced, especially your pH level.
Otherwise, spas should always have a level of 2-3 ppm of bromine, or slightly less if using chlorine. When sanitizer level drops below 1.0ppm, particles and contaminants in the water begin to run rampant or grow at a rate faster than they are being destroyed.
A proper sanitizer level should destroy the particles that induce cloudy water. To help it out, shock the spa water regularly, especially after a several people have used the spa, or if sanitizer levels have mistakenly dropped to very low levels. If a chlorinated spa shock is clouding your water, try using MPS shock instead.
3. Cloudy Fill Water
Maybe the problem is not with your spa, but in your fill water. Nonetheless, balanced and sanitized spa water with proper filtration should be able to self-correct, and clear the water within a day or so. A spa clarifier can help coagulate suspended particles for easier filtration. In most cases, it may be better to use a spa pre-filter, to remove particulates that cloud your spa water. Just attach it to your garden hose when adding water or refilling your spa or hot tub.
4. Air in the System
Small particles of air, tiny bubbles – can make the spa water appear cloudy. If your spa has bubbles coming into the returns, but your air blower and spa ozonator are turned off – you may have an air leak, on the suction side of the pump. The suction side is anything before the spa circulation pump. A loose union fitting before the pump, or a loose pump drain plug can pull air into the system.
Low water level in the spa can also bring air into the spa, and give the water the appearance of being cloudy or hazy. Inspection of the pipes and equipment before the spa pump can reveal the source of the air leak, which can then be sealed up with sealants or lubricants.
5. Spa Filter Problems
This is a common cause of cloudy spa water. A spa filter cartridge may be positioned incorrectly, allowing for water to bypass the filter cartridge. Make sure the cartridge is fully seated on both ends to force the water to go through the pleated spa filter material.
A spa filter cartridge won’t last forever, and each cleaning reduces it’s efficacy a little bit more. After about 15 cleanings, replace the spa filter and you’ll notice an immediate improvement in water clarity. Depending on how much the spa is used, and how much is asked of the filter, you should replace the spa filter every 12-24 months.
Spa filter cartridges can also become gummed up with oils or minerals, drastically reducing their filtration ability. These substances can be very difficult to remove with a garden hose alone. Spraying a cartridge in spa filter cleaner before cleaning will break down greasy or crystallized deposits, and restore full flow to your filter.
DE filters are more commonly used on inground spas, and if a DE filter grid develops a hole, it will allow DE filter powder to come into the spa. This will cloud the water, and leave deposits of a light brown powder on the seats and floors of the spa.
6. Spa Pump Problems
There are a number of pump problems that can lead to cloudy spa water, the first being the amount of time the spa filter is running each day. You may need to increase the amount of time that the spa pump operates, to increase your daily filtering time. Running a pump only on low speed can also contribute to ineffective filtration. Run it on high for at least 2 hours every day.
Another issue could be with the spa impeller. It could be clogged – full of pebbles, leaves, hair or any number of things. The vanes on a pump impeller are very small and can clog easily, which will reduce the flow volume considerably. Another possibility is that the impeller is broken – the pump turns on, but the impeller is not moving, which will reduce flow rates to zero.
If you have no flow from your pool pump, there could be an air lock, especially if you have just drained and refilled the spa. To fix an air lock, shut off the pump and loosen a union on the pump and allow air to escape, tightening it when water begins to leak. If the pump doesn’t turn on at all – well, there’s your cloudy spa water problem. There could be a tripped GFI button, loose wires, bad contactor or relay, or another control problem.
Air leaks before the pump, as discussed above, also makes the pump less efficient by reducing the overall water volume. Water leaks after the pump is also a problem, in that your water level will soon drop below the skimmer intake, begin to take on air, lose prime and stop pumping your water through the filter.
7. Biofilm Problems
Biofilm is a slimy bacteria that coats the inside of pipes and fittings. In extreme cases, it will cloud the water, and you may notice slimy flakes floating on the water, or have severe issues with spa foaming. Biofilm forms quickly in a spa that has sat empty and idle for some time. If you suspect a biofilm contamination, lower the pH to 7.2 and use spa shock to raise the chlorine level above 10 ppm. Follow this up with a treatment of Jet Clean, to remove biofilm deposits.
8. Salt System Problems
Salt systems are becoming more popular with spa owners, although they are much more prevalent on swimming pools. The issue with salt systems is that it is possible to place too much reliance on them, and never check your chlorine level. Spa salt cells also need occasional cleaning to maintain chlorine output.
Adding salt to your spa when needed may cloud your spa temporarily, until the salt becomes fully dissolved. When adding salt, be careful not to overdose, and run the jets on high for greater agitation of the water.
9. Biguanide Problems
If you use a non-chlorine, biguanide sanitizer in your spa, and have difficulty with cloudy spa water, you are not alone. This is the main complaint of using a PHMB sanitizer. You may find relief by draining and refilling the spa, and changing the spa filter, which is probably gummed up with residue. Using spa chemicals with any amount of chlorine, or using algaecides or any non-approved chemical will not only cloud the water in a biguanide treated spa, but can also create some wild colors, too!
10. Soaps, Lotions, Cosmetics and Hair Products
This problem is common to just about every spa, unless you are careful to shower well before using your spa. Everything we put on our body and in our hair can end up in the spa, and can bring oils, phosphates and detergents into the water, and a hundred other undesirable chemicals. These can consume sanitizer, clog spa filters and make the spa water cloudy and foamy. If your spa has a high bather load, or is used as a giant bath tub, you can expect issues with water clarity. Adding spa enzymes can help control greasy gunk, and reduce sanitizer demand and clogging of your spa filter.
Cloudy spa water is not so difficult to find and fix – but remember that you may have more than one of these issues working against you. Consider each cause of cloudy spa water carefully – it’s likely one or more of these situations above. Draining the spa regularly is one more piece of advice to prevent cloudy water – depending on how much the spa is used, draining it every few months is a good preventative way to keep your spa water from becoming cloudy in the first place!