Algae in my attached spa over night

[davidwest]

Hi, I turned the spa on last night to 101 degrees and noticed something different when I got in, this morning it's green!, the rest or the pool looks fine.
the water temp was in the 40's when i started to heat it. I did drain the spa the day before to get a lot of dirt out of it due to high winds.

Looks good now, I drained spa back into pool and recirculated , water turned from green to blue(clear) Maybe all the chlorine got boiled out of the spa, i checked the FC level in spa before the pump came on and in was real low, the pool was good, CYA-60, FC-7

thanks for any help

 

[pabeader]

Please take and post a few pictures. Looking down onto some feature, might be a good place to start.

 

[davidwest]

it's ok now, I drained the spa into the pool and recirculated the water. maybe all the chlorine got boiled out. I tested the FC level in the spa before the pump came on and it was real low, pool is good, FC-7 CYA-60, water in spa is blue again