Every chlorine has its pros and cons and why we use one or the other, liquid chlorine is great as its “pure” and doesn’t mess with any other chemical balance in the swimming pool. Granular chlorine is similar to liquid chlorine on a chemical level but is blended with something to make it a solid, normally stabilizer or calcium. It is important to monitor these levels when using granular chlorine for long periods of time as high calcium can cause staining and high stabilizer can cause a lot of problems. Unfortunately the only way to lower calcium and stabilizer economically is to displace the pool level with freshwater.
If you are trying to raise chlorine and have lower stabilizer or calcium sure use granular chlorine but for a maintenance dose and without affecting any other levels liquid chlorine is always best. When treating a green swimming pool depending on other chemical levels best to use granular chlorine as it is lighter to carry being highly concentrated.
The JC Pool Services Team.