Pool problem - pipe leak unlikely?

[Terratrader]

I have a 4 x 8 x 1,5 pool, installed a variable speed pump some years ago and very satisfied since I already recovered the cost from the strongly reduced use of electricity compared to regular pumps. But I seem to have a problem. I had the pump tested by a qualified pump guy and it works fine, just as I thought. However it is drawing air. I tested the valves and pipes with incense smoke to see if it got sucked in while the pump was working but no luck. At first I thought I have a leak in the pool but since the water level hasn't gone down at all, that can not be the case. I am looking for a professional to help me. The guy from Rickards construction in Pattaya hates me because I ask too many questions and even deleted me on Line recently. Anyone know a professional who can help me out? I'm at Huay Yai.

[Bagwain]

Can you see air in the lint basket, If not then why do you think it is sucking air?

[Imd8ta]

Agree with Bagwain. Check the basket on the pump suction side for air and forget the smoke test. Isolating parts of the system via valves will show leaks at connections that are pressurized.

Edited 2 hours ago by Imd8ta
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