10 Best Inline Chlorinators 2025 in the United States

The Pentair R171096 Rainbow 320 is an automatic in-line chlorinator designed for both pools and spas. It stands out for its capability to maintain consistent water sanitation, which ensures a clean and healthy swimming environment. This model is compatible with both large and small bromine or trichlor tablets, making it versatile for different pool or spa sizes. It can hold up to 11 large or 98 small tablets, which offers convenience for less frequent refilling.

The installation is relatively straightforward as it integrates permanently into the return line of new or existing systems and comes with 2” slip PVC fittings and adapters for 1-1/2” lines. However, it's worth noting that unions are not included, which might be an additional purchase for some users. Durability and material quality seem reliable given its good reviews and the fact it is made in the USA.

One possible drawback could be the lack of included unions, which might complicate installation for some users. Additionally, while the feeder is designed for permanent installation, this might limit flexibility for those who prefer temporary setups. This chlorinator is ideal for users looking for a dependable and efficient solution that offers good adjustability and ease of maintenance.

The Hayward CL200 In-line Automatic Chemical Feeder is a solid choice for maintaining your pool’s chlorine levels. Its ability to use both large and small slow-dissolving tablets provides flexibility in managing chlorine output. The dial control valve is a standout feature, making it easy to adjust the feed rate according to your pool’s needs, which is especially useful for varying pool sizes and fluctuating chlorine demands.

The Easy-Lok threaded cover ensures adding tablets is straightforward and safe, while the unique finger-release catch adds an extra layer of security, preventing accidental spills or access by children. Constructed from durable ABS material and featuring a high-quality Viton seal, the feeder promises longevity and resistance to pool chemicals, which helps in preventing corrosion.

However, it is essential to note that while the feeder is robust, the installation process might require a bit of plumbing knowledge, which could be a drawback for some users. Additionally, it is relatively lightweight at 0.25 pounds, which is good for handling but might raise concerns about its stability once installed. The product is designed to be used with tablets, which might not be suitable for users who prefer liquid or granular chlorine. The Hayward CL200 offers good adjustability, durability, and ease of maintenance, making it a suitable option for most residential pool owners looking for a reliable inline chlorinator.

The Pentair Rainbow HC-3315 is a commercial-grade inline chlorinator designed to efficiently feed chlorine into pools. It features a fully enclosed system that prevents escaping gases, making it safer and cleaner to use. The clear amber housing on some models allows easy monitoring of chlorine tablets, helping with maintenance and ensuring tablets don’t run out unexpectedly. The product is NSF listed, confirming it meets safety and quality standards. Weighing just 5 pounds and having compact dimensions, it fits most pool setups without much hassle.

This chlorinator is well suited for pool owners or operators who want a reliable, enclosed chemical feeder with easy tablet visibility and are comfortable handling some installation details. Its commercial-grade design and quality materials suggest good durability and performance under regular use.