Pebble Tec® swimming pool surfaces are very similar to plaster or Marcite. Small river pebbles are mixed with Portland cement and dye at the truck. The mix is then pumped through a hose to the pool via high pressure. The mixture is then troweled on to the pool walls and floor. After the new pool surface dries, the surface is acid rinsed to remove the thin cement covering; exposing the smooth surface and pebbles, much like an exposed aggregate pool deck.

There are a variety of colors and styles to choose from. From white to dark blue to black. Pebble Tec adds class and personality to your pool, and is a dependable long lasting finish. It also adds a naturally non-slip surface, and being made of stone, is nearly impervious to poor water conditions.

Since we wrote this article almost 20 years ago, Pebble Tec has introduced several new pool surface products to offer customers with concrete pools. Pebble Sheen® uses a finer pebble, just 1-2 mm in size, tightly fused together and buffed to a high shine. According to the manufacturer, the fine pebbles and the process of application produces a look not unlike granite countertops. Available in 16 colors.

Also now available is Pebble Fina®, which as you may guess, uses even smaller aggregate, and bits of seashells. The Pebble Fina pool surface is not unlike a quartzite finish, or plaster with bits of quartz aggregate to catch the light and add strength and durability. In addition, Fina adds pozzolans into the plaster mixture, which is a volcanic silica material that reacts with calcium to form a super strong hydraulic type of cement. The reaction continues over the years, increasing in strength over time.

Beadcrete® is another late development, licensed to Pebble Tec by an Australian producer. Instead of using only natural stones as aggregate, Beadcrete adds small, colored glass beads to produce a unique finish that shimmers and changes colors in the sunlight. With colors that range from mild to wild, Beadcrete can produce dramatic effects with incredible strength, as the tiny glass beads of 2-3 mm are locked into a matrix of aggregates and polymer modified cement. Like pozzolans, polymer-modified cements have increased strength and durability, but they also slow the rate of moisture evaporation, and give the applicators improved workability and adhesion.

In The Swim recommends that pool owners "balance" their pool water using the "Langelier Saturation Index" This system takes into account pH, alkalinity, water temperature, chlorine and calcium hardness. For the first 30 days after the Pebble Tec (or new plaster) is applied, pH and alkalinity be monitored regularly as they can directly affect the appearance of the surface. It helps to maintain levels of pH, alkalinity and calcium hardness toward the lower end of the index.

Depending on your water source; you may need to add pH reducer to your new plaster or Pebble Tec 2 to 3 times per week during the first month. After 30 days, the pool should be checked 1 to 2 times per week and adjusted accordingly. If your finish is a darker color, in particular black, it is even more important that you follow these instructions.

Brushing a Pebble Tec surface is also very important, especially during the first few weeks after application, but also afterwards, to keep dirt and algae from building up on the slightly irregular surface. Be sure to use only a nylon pool brush, never use a steel bristled pool brush on a Pebble Tec surface.

Calcium scale can dull the finish of a pebble surface. If you live in an area with hard water, a lighter color finish is recommended to avoid a whitening of the surface over time. To help prevent calcium deposits, maintain a proper level of calcium hardness, in the 180-220 ppm range. If too low, aggressive pool water can pull calcium out of the plaster, and when too high, it can precipitate out of the water and form scale. Use of a stain & scale pool chemical is also recommended for pools with calcium hardness levels over 400 ppm.

There aren’t too many disadvantages to a pebble surface; as compared to plaster (aka whitecoat or marcite). Aggregate surfaces are stronger and less likely etch, and because of the varied colors, imperfections (and dirt) are less visible. However, poor water chemistry can damage a pebble surface over time, just like any other pool surface.

The pebble surface is more textured than plaster, but not rough; the pebbles are small and smooth, however the varied surface may trap dirt, requiring extra pool cleaning. Probably the largest drawback to Pebble Tec or the other products mentioned above are cost. Elegant, sure – but it’ll cost you, roughly twice the cost of a standard white plaster job.

• Nylon Pool Brush
• Stain and Scale Chemicals
• Water Balance Chemicals