If your hot tub is not sanitized or filtered for a few days or weeks, you can see slime and algae grown in the water or in its system. So how to clean a hot tub that has been sitting? Follow these simple steps to quickly get its clean look back and enjoy your time in the hot tub with confidence.
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How to clean a hot tub that has been sitting for a while?
It’s always recommended to be careful with high-voltage appliances in your house to avoid electric shocks, and a hot tub is not an exception. That said, turn its power off and disconnect any electrical wirings before following the below instruction.
Step 1: Check the filter system
Before cleaning a hot tub that’s been sitting, it is important to inspect the filter and the pump to make sure that they are still working. Vinegar can be used to clean the filter. Simply soak the filters into white distilled vinegar for two hours.
If it’s too dirty or grimy, you might need to use solutions with special formula for hot tub filter cleanings. We would recommend you get a bucket of water filled with a cleaning solution ready before removing the filter from your hot tub. To achieve the best results, make sure you follow the suggested ratio of filter cleaner.
Alternatively, you can also use muriatic acid – a strong rust and stain remover – sold at many local hot tub equipment stores.
Once finished checking and cleaning the filter, you might want to check the filter cartridges to see if they need to be replaced. Most manufacturers recommend hot tub owners replace the cartridge every 2 years.
However, it’s best to measure the effectiveness of your cartridge by looking at the water. If it’s too dirty and cloudy regardless of regular maintenance, it’s about time for a replacement.
Step 2: Drain & Clean
How to clean an inflatable hot tub that has been sitting for several weeks? The first thing you have to do is to drain its water. This process is quite simple if your hot tub is close to a drain. If you drain your hot tub using a spigot, it will take around one hour, but it only takes around 10-15 minutes if you use a submersible pump.
All you need to do is pull the hose out so that the water can drain by itself. If your hot tub water is really dirty, you can also spray the hot tub surfaces by using a garden hose.
After draining the hot tub, rinse the hot tub shell by using a soft rag. Make sure that you only use safe household cleaners for the shell. Next, use a soft cloth to clean its outside parts. Depending on how dusty it is, you might also need to spray dust off the surfaces.
Step 3: Refill & Purge
After the unclean water has been removed, you’ll now need to purge your hot tub. This step involves the use of chemicals to remove biofilms gathered inside the hot tub pipes.
But, how is biofilm formed? It starts to form when many types of microorganisms (like bacteria and fungi) come in close contact with a suitable surface inside the piping system of hot tubs.
The longer the biofilms reside in your hot tub, the more contaminants develop in the water, and gradually affect the effectiveness of the filter.
Since biofilm is a health hazard, we would recommend you use the right biofilm cleaners to get rid of it. These products are perfectly formulated to disintegrate thin layers of biofilm while cleaning your hot tub pipes.
Simply follow the instructions shown on the labels to add it to your hot tub while the pump is running. The gunk will soon appear on the surface. You’ll then need to turn the jet pump on to remove any remaining bacteria.
Next, refill your hot tub with new water.
Step 4: Drain & Refill
In this last step, you’ll need to drain the hot tub one more time to get rid of the scum. Once you finish draining it, use a wet and dry vacuum cleaner to completely suck up the last drops of the remaining water.
Now you can refill your hot tub with fresh water. After it is full, you’ll need to test the water chemistry and add chemicals to maintain the balanced pH level. Lastly, shock the hot tub to kill bacteria and keep the water clean and safe.
How to get rid of black mold in a hot tub?
Hot tubs can easily get moldy and it can negatively impact water hygiene. Even worse, it could lead to long-term damage to the shell and the hot tub cover.
Mold usually forms in old or neglected hot tubs. Skin cells of the bathers, lotions, and soaps are common causes of mold. But sometimes mold can also grow by itself. It usually starts to grow on the cover and spread to the shell, then the water.
It’s best to clean your hot tub regularly to prevent mold. But, if you start to see black specks on its underside, take action as soon as possible to prevent it from spreading to other spots of the tub.
When black mold shows up on the tub’s cover, you’ll first need to remove the cover, then clean it thoroughly by mixing warm water with the dishwasher. If it’s heavily molded, replacing another cover would be a better idea.
A soft brush can also help you to clean the mold. Once finished, spray it to completely remove cleaning solutions from the surface. In case black mold appears all over your hot tub, mix bleach (instead of dishwasher) into warm water to remove it.
So, how do you clean a hot tub that has been sitting? We hope we have provided you with some useful step-by-step instructions, so you can start working on it yourself without calling a local cleaning agent.
You’ll first need to check the filter, drain the hot tub, then purge it to control biofilm. Once sanitizing and draining is done, simply refill and add necessary chemicals.