How to Add Algaecide to Pool? Best Method Explained
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Table of Contents
How to Add Algaecide to Pool?
Wish you knew how to add algaecide to pool water to keep it clean and sparkling.
Algaecide works best in tandem with chlorine. Chlorine is the main algae killer, but algaecide supports chlorine by making the algae weak & vulnerable.
Adding Algaecide to your pool regularly, every week, as well as on some special occasions will prevent algae growth. However, adding algaecide without proper circulation will not be effective.
After adding algaecide run the pool pump for 2-4 hours to ensure it is broadcast throughout the pool.
Do you Run the Filter while Adding Algaecide?
Are you in the habit of adding Algaecide every week, without fail, to your swimming pool? If so, then great! You have got the health of your pool covered. But do you run the filter & pool pump while adding the Algaecide?
It is very important to run the pool filter & pump while adding Algaecide. It is best to start the filter pump just before adding Algaecide and let it run for 2-4 hours to ensure adequate circulation.
The setting on the filter will depend on the state of algae in your pool and the type of filter that you are using. It will also help in ensuring that your pool filter does not clog up with excess algae.
In this post I will explain the filter settings for different algae status and the timing of the addition of the Algaecide to the pool.
Should I Backwash after Adding Algaecide?
The decision to backwash a filter depends on the amount of clogging of the filter material.
Sand Pool Filter
The normal pressure gauge reading for a Sand Pool Filter is between 10-20 psi, when the sand is clean. It is time to backwash the sand filter when the reading goes up 10 psi above the normal.
DE Pool Filter
Similar to a Sand Pool Filter, it is time to backwash a DE Pool Filter when the pressure gauge reading is 10 psi over the normal reading.
Cartridge Pool Filter
Cartridge Pool Filter can not be backwashed. Instead the cartridge needs to be cleaned once the reading on the pressure gauge hits 10 psi.
Actually, if it is time to backwash a Sand or DE Pool Filter, it is best to do it before adding Algaecide. That way you will not lose costly pool chemicals.
What Should My Pool Filter Be Set On?
The setting on the pool filter while adding Algaecide will depend on the state of algae in your pool and the end result you are targeting for.
Pool Filter Setting Options
A pool filter with a multi-port valve has several settings. For example, the Hayward Pro Series Pool Sand Filter, comes with a 7-way multiport valve.
The 7-way Multi-port Valve Positions are Filter, Waste, Winter, Closed, Backwash, Recirculation and Rinse. This is what each of the settings mean:
Filter
The main reason for having a pool filter is to trap and remove unwanted debris and contaminants in your pool. So it is not surprising that your pool filter is almost always on the Filter setting.
Waste
The Waste setting allows the pool filter to suck in the pool water. However, the water is not filtered and recirculated. Instead it is discharged to a drain or in the yard.
Waste setting is convenient when vacuuming the pool floor. Quite often you do not want the larger debris on the pool floor such as “dead algae”, leaves etc. to clog up the filter material.
Of course, you do lose pool water and pool chemicals in this setting. So they have to be replaced.
Backwash
In the Backwash setting the flow of water is reversed. This setting is used periodically to clean a sand or DE filter when they get clogged.
The dirty water does not obviously go back to the pool. Instead it is released into a drain or in the yard.
You do lose some pool water and pool chemicals during Backwash.
Rinse
The Rinse setting should be used after every Backwash. It cleans out the filter medium before the valve can be set back to Filter mode.
Recirculate
The Recirculate setting is a bit like the Waste setting. Pool water is sucked in but does not go through the filter medium. It does not go to a drain or yard either. It goes back into the pool.
The Recirculate setting is useful when you need circulation but do not want filtration.
Running a cartridge filter without the cartridge is the same as running a sand filter or DE filter on Recirculate position. The pool water bypasses the filter in both cases.
Winter
The Winter setting is used when you close the pool for winter. The winter setting allows space for any water left inside the valve to expand when it freezes.
Closed
The Closed setting is rarely used. When the multiport valve is on the Closed setting, water can not enter the pool filter.
Filter Setting While Adding Algaecide
So what should be your filter setting be while adding Algaecide to your pool? Below is the guideline for three common scenarios.
Adding Algaecide During Regular Weekly Cycle
You should brush your pool at least once a week. Once the brushing has been done check the amount of debris and algae on the pool floor.
Do you need to vacuum? If so then the pool filter setting will need to be on Waste. Whatever the vacuum collects then goes completely out of the pool’s system.
Next check the pressure gauge on your pool filter. Is it almost time to Backwash? If so, Backwash and Rinse the filter before adding Algaecide.
Change the setting to Filter and start the pool filter pump. Add the Algaecide in a few places along the perimeter. Run the filter for 2-4 hours.
Ideally this should be done in the evening after you are done using the pool for the day. The running of the pool filter will ensure that the Algaecide has been distributed over the entire pool.
The Algaecide will be at work during the night. The pool will be ready for you next morning.
Adding Algaecide After Shock
Ideally you should shock your pool every week or at the very least once in two weeks. The procedure and the settings will be the same as above before you add the shock.
The pool filter should be run for at least 24 hours after adding shock. Add Algaecide only when the free chlorine level has dropped to 5 ppm or less.
Balance your pool for pH, alkalinity and calcium hardness. Run the pool filter for 2-4 hours.
Adding Algaecide Before a Rainstorm
Adding Algaecide before a rainstorm will prepare your pool for the algae onslaught that rain water and high winds will dump on your pool.
Prepare your filter too by backwashing a sand or DE filter or cleaning the cartridges of a cartridge filter.
Add Algaecide and run the pool filter for 2-4 hours.
Recommended Swimming Pool Chemicals
Algae Guard Ultra (Algaecide)
HTH 67089 Swimming Pool Care Algae Guard Ultra
The non-foaming, non-staining and fast-acting formula both kills and prevents extreme amounts of stubborn green, black and mustard algae for a season of crystal clear pool water and offers up to 3 months of protection.
Cyanuric Acid Free Shock (Cal Hypo) – Powder
HTH 52037 Pool Care Shock Advanced
A fast-dissolving, convenient 4-in-1 Cal Hypo formula that kills bacteria & algae, reduces chlorine odor & irritation, and quickly restores crystal clarity.
Thank you very much for reading the post. I do hope you found it informative and helpful.
