The chiller was new when I bought it never used in a salt water tank.
I opened the box which came from the importer.
This tank has 80% RO.
I was warned against tilting the chiller in the very beginning coz it damages the chiller.
I will try the vinegar method to clean the chiller internally.
But it seems I'm going to need a lot of vinegar solution.
As for dust and dirt I have no choice but to open the screws and suck the dust with a vaccum.