Metal Free is a bogus product, based on citric acid. You could call citric acid "Chlorine-Free" since it destroys chlorine and is destroyed by it. It's a low grade version of ascorbic acid. Ascorbic acid is ALSO incompatible with chlorine, which is why our guides have you dechlorinate and use polyquat FIRST.

Why in the world did you put Metal Free in? Pour any you have left down the toilet and flush it away!

Turn your pump on 24/7, get your chlorine back up to at least 10% of your CYA level, and use the polyquat if you have any remaining trace of algae. Polyquat will ALSO use up some chlorine -- but it is transformed into another form that STILL helps with algae.

Get your pool back to algae free and correctly adjusted with respect to chlorine, pH and alkalinity. Keep your pH at the low end of the range.

Then, see if any stains have returned. Unfortunately, it often takes several cycles to actually REMOVE the metals from your pool. Stain removers like ascorbic acid just MOVE the metals from the pool surface back into the water. You STILL have to get the metal OUT of the water. The CuLator packs do that, but only slowly.