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5 Best Pool Chemicals in 2021 – Reviews & Top Picks

Last Updated: June 6, 2021

Blue Wave NY976 Pool Chemical Spring Start-Up Kit

When the winter months end and the cold weather starts to dissipate, your pool is full of contaminants that have been growing all winter long. These unwelcome guests need to be eliminated before you begin enjoying your pool for the year. Who really wants to swim in a green pool? Very few people have any interest in that. If you needed to piece together your start-up kit from separate, individual chemicals, it could be a long and arduous process requiring significant knowledge of pools, water, contaminants, and chemicals.

Luckily, manufacturers have taken all the guesswork out of the equation by providing us with ready to go start-up kits that include everything you need to get your pool up and running for the spring and summer months. But what kit is the most effective and easiest to use?

We wanted to answer this question, so we set out to test all the best products on the market. The following five reviews will compare what we learned during our testing to help make the decision easier for you as well.

A Quick Comparison of Our Favorites

Image Product Details
Best Overall
Winner
Blue Wave Blue Wave
  • Pre-formulated
  • Three pool sizes to choose from
  • Great for opening your pool
  • Best Value
    Second place
    In The Swim In The Swim
  • Affordably priced
  • Cleared out the green color
  • Kept pool water crystal clear
  • Third place
    Rx Clear Spring Rx Clear Spring
  • Includes chlorine shock
  • Comes with everything you need
  • Low-cost
  • Doheny's Swimming Pool Start-Up Doheny's Swimming Pool Start-Up
  • Comes with everything you need
  • Good instructions included
  • For pools up to 30,000 gallons
  • Spa Frog Hot Tub Spa Frog Hot Tub
  • Includes PH balancers
  • Perfect for opening your hot tub
  • For hot tubs of 500 gallons
  • The 5 Best Pool Chemicals – Reviews 2021

    1. Blue Wave NY976 Pool Chemical Spring Start-Up Kit – Best Overall

    Blue Wave NY976

     

    When it’s time to shock your pool and clear out all the contaminants that have been growing and festering over the winter months, our favorite product for the job is the Blue Wave NY976 Pool Chemical Spring Start-Up Kit. It contains everything you need to treat your pool and open it for the season. Even if your pool is green with algae or the water is murky and dark, this kit will take care of it and leave you with a perfectly clear, swimmable water.

    This kit contains algaecide, a clarifier, rust and scale remover, and shock treatment as well. It’s available in three different sizes to clean out pools of different sizes. You can purchase these chemicals sized for pools of 7,500 gallons, 15,000 gallons, or 30,000 gallons. Each kit contains the right amount of each chemical to clear a pool of the designated size, so there’s no guesswork involved. It’s all pre-formulated and pre-measure, making your job very simple. However, you’ll have to balance the PH before beginning your shock treatment. The lack of directions also made things a bit more difficult, but our pool ended up so clean and clear that this product is our favorite.

    Pros
    • Pre-formulated and pre-measured
    • Three pool sizes to choose from
    • Great for opening your pool at the start of the season
    Cons
    • Must balance PH first
    • No directions included

    2. In The Swim Basic Pool Opening Chemical Start-Up Kit – Best Value

    In The Swim Basic Pool

     

    For an affordable yet effective pool opening chemical start-up kit, we suggest this package from In The Swim. It contains everything you need to open your pool for the season, even if the winter months resulted in a murky green pool. Our pool was very green and nasty when we added these chemicals at the start of spring. A few short days later and our pool looked like it was brand new. The water was crystal-clear and devoid of any unwanted colors or smells. It even includes four-way test strips so you can be certain that everything is working as it should.

    Each chemical has directions for its proper use, but the kit as a whole does not have any instructions. This made it a bit confusing since we were wondering if the chemicals could all be applied at once or if there was a specific order or wait time that needed to be used. Some clearer instructions on how to use the kit as a whole would have been appreciated. Despite this, the low price and clear pool water we got from this product make it our choice for the best pool chemical for the money.

    Pros
    • Affordably priced
    • Cleared out the green color
    • Kept pool water crystal clear
    Cons
    • Directions for individual chemicals but not for the kit as a whole

    3. Rx Clear Spring Pool Start-Up Kit

    Rx Clear Spring

     

    The Rx Clear Spring Start-Up Kit is a low-cost and effective way to prep your pool for the spring and summer swimming months. This kit includes a strong chlorine shock to get the jump on anything living or growing in your pool after winter. Many kits don’t include this chlorine shock, but it’s necessary to oxidize and purify the water. Beyond the shock treatment, this kit has everything you need for clear and refreshing pool water including algaecide, stabilizer and conditioner, and test strips to ensure that all of your levels are proper.

    This kit even included good instructions that made it clear what steps we needed to take and in what order. But the algaecide left our pool foamy for days on end. Naturally, no one wants to swim in a foamy pool that’s full of chemicals. Once the foam dissipated everything was fine, but it was still very off-putting to see the pool full of so much foam after using this start-up kit. This kit comes in three different sizes for treating above-ground and in-ground pools up to 30,000 gallons in volume and it’s one of the more affordable choices on the market.

    Pros
    • Includes chlorine shock
    • Comes with everything you need to open for the season
    Cons
    • Algaecide made the water foamy

    4. Doheny’s Swimming Pool Start-Up Kits

    Doheny's Swimming Pool

     

    If you don’t mind paying a bit more for your start-up chemicals, then the Doheny’s swimming pool start-up kits are an option you may consider. They’re sized for pools up to 30,000 gallons, and there are two options to choose from for large pools of this size. The Pro’s Choice Master Kit offers upgraded enzymatic formulas of each chemical for an increased price. But even the regular start-up kits from Doheny’s are more expensive than competitors.

    We were impressed with the good instructions included with the Doheny’s kit. Everything was easy to understand and ensured that our pool opening went smoothly. Everything you need to get your pool open for the season was included, and it was a relatively quick process to get it started. In no time, our pool looked clear and ready for use. But we got similar results from other products that cost considerably less, which is why the Doheny’s start-up kit is placed lower on our list. We didn’t notice anything special about it that justifies the higher cost.

    Pros
    • Everything needed for opening
    • Good instructions included
    Cons
    • More expensive than other options

    5. Spa Frog Hot Tub Start-Up Kit

    Spa Frog Hot Tub

     

    Most of the start-up kits that we tested for this list were available in multiple sizes to fit different sized pools. The Spa Frog kit is intended just for hot tubs though, and it comes in only one size. This one is meant for hot tubs of 500 gallons. If your hot tub is less than that, then you’ll need to adjust accordingly by simply using less than the included amounts of each chemical. Everything you need to open your hot tub for the season is included. You’ll get a shock treatment, PH balancers, a jump-start product, and even test strips to ensure that all your levels are set correctly. To top it off, you get a free-floating dispenser that will keep your hot tub water in good condition.

    This kit seems a bit overpriced for what you get, especially when you compare it to the pool kits that can treat 30,000 gallons of water. But it does make the entire job very simple and includes everything you need in one easy package. Plus, it’s also a great choice for small pools that don’t reach the 7,500-gallon mark that the other chemical kits start at.

    Pros
    • Includes PH balancers
    • Perfect for opening your hot tub
    Cons
    • Only one size
    • Overpriced

    Conclusion

    No matter how large or small your pool is, it’s going to require some maintenance after the winter months have allowed ample time for growth and contamination inside. Unless you want to swim in a green pool that looks more like a pond than a beautiful backyard amenity, you’ll need a start-up kit to clear out the nastiness and get the water ready for swimming. Our reviews compared five of the most popular chemical start-up kits on the market, but two of them really stood out to us during our testing as the best performers of the group. The Blue Wave pool chemical spring start-up kit was our favorite. It comes in three sizes for treating pools up to 30,000 gallons, and everything is pre-formulated and pre-measured simplifying the process and removing all the guesswork.

    For the best value, we recommend trying the basic pool opening chemical start-up kit from In The Swim. Despite being more affordably priced than competing products, it cleared out all the green from our pool and returned the water to a crystal-clear state free of odors and unwanted contaminants. Both of these products were top-performers and we feel confident giving them our recommendation.