FC still there after first opening of the season

[linuxninja00]

Hello fellow TFP'ers,

First time occurrence for me, but I still have FC in the water after pulling the cover off. TFT kit registered 5 FC in water that was previously 85 CYA before closing. Water is clear barring some leaves I didn't completely get out and a little algae on the stairs that was above the water level after closing. Prior to closing I raised to SLAM levels, let it drop a tad and shut her down. Is it not out of the ordinary to have some FC left after winter upon opening? Did I just do an amazing job closing her down?

Thanks,

Eric

 

[JamesW]

If you have a solid cover, it's very possible to have chlorine last all winter.

 

[linuxninja00]

If you have a solid cover, it's very possible to have chlorine last all winter.

I do, solid Merlin cover. Even after all the rain and unusually large amount of snow this winter, the water level was where I drained it.