On Demand Heater For 1000 gallon Pool?

New guy here.
I own a Flowclear 1500 galllon above-ground pool pump
and an
Intex 9.8’ x 79" x 29.5" Rectangular Frame Above Ground Pool

I have this set up in my basement which is already warm. I need
to warm the water just a bit I believe.

In summer I swim local lakes when the lake temp is 65 degrees on up and only need 68 or so degrees. I swim 20 minutes often twice a day. I have a bunji harness which will allow me to go forward a bit and it will pull me back.

I was told try an on demand heater since I dont require much water heat.
Anyone using on demand for small pools and such and could suggest what I need to buy?

Thanks for any advice

Hi Biodad and congratulations on your diligent exercise routine!

Something like this HydroQuip Heatmax RHS 11kW Remote Electric Heater System, 230V, Weather-Tight, - RHS-11.0 would be an excellent way to heat your water (it will heat it at the rate of a little more than 1 degree per hour) to the temperature you want. It just needs 230 volts hooked up to it to get the temperature where you want it to be and the thermostat is built-in. Add some valves before and after the heater so you can service it without draining the pool. We may have other fittings you need in our Softside Pool Accessories section.

I will look into this.Thank you