I brought my Arowana home yesterday. He was moving in the whole tank but today in the morning I switched on my tank led light and he got scared. After that I switched off the light and now he's swimming only at one side. My right side of 4ft tank has a power filter. Is he afraid of the flow coming out from the filter? My left side has a heater placed with 28°C temp I have swtiched off it yesterday as the water felt warm to my hands. What to do?