Quote Originally Posted by giantsnation View Post
After talking to my brother-in-law who has a tablet chlorinator, I think this is the way to go. I did a lot more digging about tabs and related high CYA issues and found that it is not as much of a problem up here in the northeast. WHY? Well, most of research concluded that by the time the levels get to "too high", we're closing the pool and thus, drain a majority of the water and winterizing. With my Sand filter (same as my brother-in-laws), I was told that I should get a small bucket of granulars. That is what he adds once or twice a week. He said between the granulars and the tabs, his pool always looks clear, sparkles and tests well (within acceptable ranges).

Additionally, at a cost of $65 for the rainbow 300-29, I don't see how I can go wrong. I'll get this add tabets and test daily. When I need more FC, I'll add granulars. Typically, I backwash the pool ~ once a week and clean the pump skimmer twice a week.


Also, the rainbow 300-29 has been confirmed as an OFF-LINE model.
As I said, with a sand filter the use of trichlor tabs can be a successful way to provide a background level of chlorination as long as an unstabilized chlorine source is used in addition such as the cal hypo granules you mentioned.(Do not use dichlor since this is a stabilzied chlorine source. Sodium hypochlorite is also useful as a supplimentary chlorine source. Lithium hypochlorite is just to darn expensive!). The fact that you live in an area with a very short swim season and winterize means the CYA will not get a chance to rise much over the swim season. Toward the end of the season you might need to add some polyquat or youmight want ot add borate to 50 ppm at the start of the season. Either will providethe algae control that might be needed without any problems. However, this is not what most of the pool owning populaton experience since there are far more pools in warmer climates that do not winterize so the use of trichlor becomes a major problem. Where I live pools are open year round so trichlor use is not a first choice for chlorination.

As far as the chlorinator goes, The Rainbow 300 series of offline feeders by Pentair are, IMHO, the best offline feeders on the market. The 300-29 is listed a spa feeder, the 300-29K is the commercial feeder with the larger chamber that dispenses more sanitizer at a time for large commercial pools over 80k gallons. If you consult the online Pentair catalog they have info and manuals on the different models. The larger sizes (and the extension tubes to increase capaicity) are for dispensing more chlorine for a larger sized pool, not so you don't have to fill them as often.