Re: plugged fitting,need solution

[aquasonic]

If the supply is clogged that badly, then the top really should come off the tank in order to clean the intake screen and tube. The tank most likely needs a good cleaning inside anyway.

As others have mentioned, you can safely apply heat to the screws by washing out the tank several times, filling it with water, and leaving the cap off. Those screws will come loose with enough heat, penetrating oil, and use of an impact driver. It may take a few cycles. Go slow.

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