Gave you a merit as the image posted means you did an effort to show how it works
2500 watts = around 8500 btu it may be enough for the pool
Thanks! Hopefully so, I assume running 24/7 it'll warm it up a bit, maybe make it usable in summer.
Today's my first day long term testing, had router issues.
If you cover it at night it will get warmer faster and hold the heat better.
Even a lower cost tarp will help.
I used two sections of pipe to get it wide enough bolted the tarp to it.
rolled it up and attached one end of the tarp to a safety fence.
then unrolled it . the tarp wont last a long time , but its a cheap fix to get the pool heated up.
and keep it hot over night if you get cool at night.