Question about Intex Solar Mat

The mat is approx. 1m2 in size, in the best case this results in a heating capacity of just under 200W with full, straight sunlight. Your pool can hold approx. 2000L. Heating 2000L by one degree requires about 2000W for one hour. So, as a rule of thumb, a mat can heat the pool by 0.1 degrees per hour. Plus the direct heating of the pool of course.
I heat up a children's paddling pool with about 200 litres with 2 mats, which is quite fast, theoretically about 2 degrees warmer per hour. Plus the 1.5 m2 surface of the paddling pool, which also brings about 1.5 degrees per hour. 10 degrees warmer in 3 hours with just under 200 litres is fine.

I had 3 solaarmats connected one after the other. After the first heated water is out of the mats, you have to stop the filter pump again and again and let it heat up again. (in summer for at least 30 minutes).
My tip: Cover the pool properly at night so that the water cools down a little overnight, the sun does the rest the next day and the water is around 30 degrees at 3 p.m. ;-)