If your test strips are actually correct, your water is not good for shrimps because there’s barely any minerals in it. You GH looks to be close to 0. Get a proper GH/kh test kit for better measurement. You’ll likely need to remineralize. Aim for 100+ for GH.
Commercial_Wasabi785 
A heater can’t heat the water more then it’s set temperature. Laws of Physics and whatnot.
If your test strips are actually correct, your water is not good for shrimps because there’s barely any minerals in it. You GH looks to be close to 0. Get a proper GH/kh test kit for better measurement. You’ll likely need to remineralize. Aim for 100+ for GH.