Hi there. i am babysitting my Dads 2 fish tanks. His smaller Juwel tank has got quite warm. The thermometer says 30c, pushing 32?? Is this because the room temp is quite hot due to the heatwave? The room does get sun all day long. The heater seems a basic 50w Juwel one with no thermostat, well i cant see an idicator anywhere. The dial on top doesn't have any markings so i dont know which way is up or down?? The fish are just hanging around at the bottom of the tank. There is movemnt in the tank from the filter. Any ideas?