Tips on How To Remove Calcium from Pool Tile

This article provides tips when using Piranha Descaling Gel to remove calcium deposits from your tile or stone around your pool or spa that will help you make your project a success.

  1. Always wear eye protection and rubber gloves – The Piranha Descaling Gel is a strong acid to be effective in removing the calcium.  The acid is highly corrosive and will burn your skin and damage clothing and other surfaces.  FOLLOW ALL THE INSTRUCTIONS FOR PROTECTING YOURSELF BEFORE STARTING THE PROJECT.
  2. Lower the water level – You will want to lower the water lever a few inches to fully expose the calcium on the water line.  NOTE:  You may want to keep the water line above the plaster or pool surface as the acid may react with these surfaces and may etch or lighten the color.  TEST IN A SMALL INCONSPICUOUS SPOT TO MAKE SURE YOU GET THE DESIRED RESULTS.  EVERY POOL SURFACE IS DIFFERENT AND WE TAKE NO RESPONSIBILITY FOR THE EFFECTIVENESS ON YOUR SURFACES
  3. Let the Acid Do the Work – The calcium has a high PH and the acid has a low PH.  When combined they will react and the acid will bubble and fizz so that you know it is working.  As they come together they will neutralize each other and you may need to stir it or add more acid to refresh the interface between the calcium and acid.  I recommend applying with a cheap “chip” brush that you can get for < $1 at any home store.  I brush a thin layer on the calcium and generally let it do the work for 7 -8 minutes then brush with a disposable stainless steel brush to remove any calcium that will scrub off and refresh the surface with more gel if required.  For maintenance applications I find one or 2 cycles of 7-8 minutes will remove the calcium.  If you have very heavy calcium deposits that have accumulated over years you may want to try to chip off with a putty knife prior to using product.  The acid in the Gel will etch, but may take considerable time and multiple applications to etch very thick calcium.
  4. Pay attention to your grout – The acid will react with most grout, but would only etch microns away during routine cleaning, but every grout is different so either apply around the grout or monitor the grout to make sure it is not etching too much away.  If you desire to clean stains from the grout, you can try applying to the length of the grout line to get a consistent color match as the acid etches and essentially cleans the grout.  ALWAYS test on an inconspicuous area to ensure you get the desired results.
  5. Do Not Let the Gel Dry on the Surface – The Gel is a thickening agent to hold the acid on the surface.  “Kinda like corn starch and water” If you let it dry or bake on the surface then you will have a new challenge to remove the Piranha Gel from the surface you are cleaning.  Do 8 – 10 foot sections that are not in the direct sunlight and move around the pool.  This also gives you many opportunities for breaks. Before moving to the next section rinse off the surface and brush or wipe down the surface to be sure you remove all the product from the cleaning surface.  It is OK to rinse the product into the pool.  The remaining acid will have a minimal affect on the PH of your pool water related to the volume of your pool.
  6. If you have lots of calcium – If you have a thick layer of calcium it may take additional applications to completely remove.
  7. Thoroughly Rinse Off – As mentioned above you want to remove all the Piranha Gel before it dries on the surface.
  8. Manage your Pool Chemistry – Once you have cleaned the calcium you will want to manage the chemistry and PH of your pool water to help have proper levels of minerals in your water to minimize the return of the water line.

We hope these tips will help you with your project.  There are many ways to tackle the problem with calcium on the water lines of your pool that involve bead blasting, using pumice stone or other abrasives to remove mechanically.  We believe that letting chemicals do the work is the easiest and least damaging to the surrounding areas for most applications.  To purchase product or get more information go to our Products page.