I have read several posts regarding converting from Baquacil to chlorine. In the fall when winterizing I empty my sand filter prior to bringing the pump assembly indoors for winter. I want to convert this spring. I read about changing the sand after the conversion, but do I need to fiil my filter with sand, then convert, then change sand or can I convert, then add new sand? Also I plan on buying the TF-100 test kit, but does it measure the bacquacill content? If not, how do I measure? Just need a little help. Thanks.

Welcome to TFP!

You can do the conversion without a filter at all, but it will go more quickly if you fill with sand, and then replace the sand afterwards. The one thing you don't want to do is to use the filter without sand in it, as that could permanently clog the laterals.

The TF-100 will not measure the baquacil level. If you are doing a conversion there is no need to measure the baquacil level.

If you haven't already, you should read the conversion instructions at Pool School, see the large button near the top right of every page of this site.

The only thing a measurement of the Baquacil levels will tell you is a rough idea of how much chlorine will be needed for the conversion and how long it will take, but unless you were planning on intentionally doing a partial drain/refill to lower the Baquacil level, then it's a moot point.

When doing a conversion, you will need plenty of reagents. Be sure to get extra R-0870 and R-0871.

I believe one key factor to converting is to start the conversion at the startup in the spring. After closing the pool last fall, with the pool sitting all winter, all the baquacil was gone. During the conversion, the only color change was a slight greenish yellow tint. I added bleach all day yesterday, pretty much hourly, then last night checked the FC and added enough to get the FC back to 15ppm. Checked the FC this morning, and FC was 14.5. I dumped the sand in the filter, found no Baqua-goo. I have now refilled the filter with sand and ready to add the CYA. I may be wrong, but from this experience, I came to the conclusion that the baquacil must have been zero or close to it, so no goo and cleaner conversion. Comments?

Certainly lower baqua levels helps the conversion go more quickly, and the easiest way to have low levels is to do the conversion in the spring.