De filter grids + acid?

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Generally, acid is not required or even the best way to go at first. You don't want to use acid without first using a degreasing product like TSP. Organic oils on the filter can harden and permanently damage the filter if they are still there when you use acid. Usually TSP, or automatic dishwashing detergent, is enough to take care of everything. But if you have calcium scaling on the filter you follow the TSP with acid to remove the calcium buildup.