Pebble, Quartz, and Aggregate Pool Finishes: Care, Chemistry, and Longevity

A pebble pool that got a real startup still looks poured-yesterday at year twelve — one that got a splash-and-dash startup looks tired by year three, and no amount of brushing brings it back. I've been on Florida pool routes since the late 1990s, and my father — a licensed Florida pool contractor since 1989 — taught me aggregate care back when Pebble Tec was still the new thing on the block.

What counts as an aggregate finish

Pebble, quartz, and exposed-aggregate finishes are the premium category of pool interiors. Pebble Tec and its competitors (Pebble Fina, Pebble Sheen, Stone Scapes) are marble-based aggregate with colored pebbles troweled onto the shell. Diamond Brite and Hydrazzo use a similar process with quartz or marble chips. These finishes cost 20–40% more than plain plaster and last 15–20 years instead of 7–10.

Do that math before you flinch at the quote. A plain plaster resurface in South Florida runs $7,500–$12,000, and at a 7–10 year lifespan you're buying that job twice in the window one aggregate finish covers. Pay 20–40% more once, or pay full price twice. That's the whole pitch — and for once, the pitch is honest.

How aggregate finishes are applied

The process is similar to a plaster application but with aggregate mixed into the marble-cement base:

1. Shell prep — bond coat troweled onto the gunite.
2. Aggregate finish troweled on at approximately 1/2" thickness.
3. For pebble finishes, the surface is acid-washed or pressure-washed after initial set to expose the pebble texture. For quartz/aggregate, the surface is polished smooth.
4. Pool is filled and startup chemistry begins immediately.

Step three is what separates the texture families: washed surfaces keep the pebble underfoot, polished surfaces feel closer to classic plaster.

Common aggregate brand families

Why owners call them “low maintenance”

• Texture hides minor stains— small algae spots or light calcium scale are visually masked by the variegated surface.
• Durability— aggregate is harder than plaster and resists the year-to-year spot etching that plain plaster develops.
• Color permanence— aggregate colors are locked in with stone, not pigmented plaster. They don't fade like colored plaster.

Half true. The finish forgives cosmetic sins — it does not forgive chemistry sins. It just hides them until they're expensive.

The service-tech reality

Aggregate finishes have their own care profile, not just “set and forget.”

• Calcium hardness matters more, not less. The marble cement that holds the pebbles in place dissolves in acidic, calcium-starved water. Keep calcium hardness above 250 ppm; keep pH from dipping below 7.2.
• Brushing is different. Soft nylon on pebble works; stiff nylon or metal on exposed aggregate scratches the cement matrix and loosens pebbles.
• Pebble loss over time.Even properly maintained pebble finishes shed some pebbles annually — normal wear. Persistent loss over a small area points to localized chemistry issues.
• Scale shows differently.Calcium scale on pebble looks like white film in the cement matrix between pebbles; on plain plaster it's a uniform whitening. Different diagnosis, different treatment — our scale and etching guide covers both.

Startup chemistry — the first 30 days buy the next 20 years

The first 28–30 days set the trajectory for a pebble pool's 20-year life. Our 30-day startup playbook has the full day-by-day sequence — these are the aggregate-specific moves:

1. No chlorine for the first 48–72 hours. The exposure acid wash or pressure wash leaves acid residue that drives pH low; chlorine added to low pH is corrosive to the aggregate.
2. Brush twice dailyfor 14 days. Removes plaster dust before it permanently stains — technique and brush choice are in our new-plaster brushing guide.
3. pH stays 7.2–7.6, never below 7.0. Aggressive LSI is the single biggest threat to aggregate startup.
4. CH stabilizes at 300–400 ppm during the first month.
5. Avoid granular chlorine and salt cells for the first 30 days. Concentrated chemistry on the fresh surface etches locally.

If your finish is Diamond Brite, there's a warranty angle on top of the chemistry — our Diamond Brite startup guide covers who's responsible for what.

What South Florida does to aggregate finishes

Down here the finish never gets an off-season. Three local realities change how you run a pebble pool:

• Evaporation concentrates calcium. Year-round heat pulls water out of the pool and leaves the calcium behind, and on pebble that shows up as white film creeping through the cement matrix between the stones. Watch the film line, not just the test kit.
• Summer storms swing the chemistry. A wet-season afternoon dump dilutes everything you balanced that morning. On a fresh aggregate surface during startup, retest after heavy rain instead of waiting for the next scheduled visit.
• Salt systems are everywhere.Fine on an aggregate finish — after the first 30 days. Keep the cell off during startup, no exceptions.

Aggregate pools are one place the extra effort during startup pays back for two decades. A pebble finish that was started badly looks mediocre for the rest of its life. One started well looks like the day it was poured for 10–15 years.

When to call a pro

Call when the surface tells you something is off: pebbles shedding from one concentrated spot, white film spreading between the stones, rough patches you can feel through the brush pole, or a fresh finish about to be filled without a real startup plan. Every one of those is cheaper to fix early — and the startup window doesn't reopen. If your pebble or quartz pool needs a diagnosis or a proper 30-day startup, book a repair and startup visit and we'll put eyes on it.