Water tank, balance tank and pond waterproofing
Tanks and ponds hold water all the time, so a small crack soon becomes a steady loss. Pebble Pools waterproofs concrete water tanks, balance and surge tanks, ponds and water features in Phuket and across Thailand.
Upgrades & repairs for hotels and villas · Waterproofing
What we waterproof
Tanks and ponds are close to our pool work. They use the same concrete, need the same care at joints and fittings, and have to hold water day after day. Pond and tank waterproofing without tiling is possible on a concrete base; a pond built on a flexible liner cannot be waterproofed by us.
- Concrete water storage tanks, above or below ground
- Pool balance tanks and surge tanks, including tanks with corroded or cracked walls
- Concrete-based koi ponds, reflecting ponds and garden ponds
- Waterfalls of any kind — natural stone, lit waterfalls, water curtains and cascades — along with channels and other water features
Systems we use
We choose the type of system for each concrete structure after inspection.
- Rigid cementitious waterproofing for concrete tanks and shells where the base does not move
- Coatings for concrete tanks and ponds that hold up in the open sun without a protective covering
- For concrete ponds, coatings that can also carry colour, so the waterproofing becomes the finished surface without tiling
- Negative-side waterproofing for tanks below ground where groundwater presses in from outside
Balance and surge tank repairs
A leaking balance tank can drain a pool without anyone seeing the water go. We inspect the tank walls, floor, corners and pipe entries. Corroded walls can be replastered and reinforced at the corners before the waterproofing goes on. If the old tank is too damaged to repair directly, a tank-in-tank rebuild may suit: a new tank formed inside the old one. In difficult cases, a tank-in-tank approach can also be used for a pool.
Planning the work
Tanks and ponds must be emptied and dried before waterproofing. Not every hidden problem can be seen at once, especially when a tank or pond's history is unknown, so testing and restarting after repairs may go in stages. For ponds with fish and plants, we agree with you how they are moved and kept during the work. For storage tanks, we agree how the property's water supply is managed in the meantime. Incoming water filtration can be added at the same time; see Incoming water filtration (water-filtration).
Related pages: Pool leak repair & waterproofing (leak-repair-waterproofing) and Basement, pit and pump room waterproofing (below-ground-waterproofing).
What to send for a first discussion
For a first discussion and a quotation, send us:
- Photos of the tank, pond or water feature, inside and out where possible
- The property location in Phuket or elsewhere in Thailand
- The approximate size and depth, whether it is above or below ground, and confirmation that the base is concrete
- How much water it loses, and any cracks, damp or past repairs you have noticed
Where we have done this
- Private Villa, Bang Tao — Black Granite — The surge tank had been leaking badly and its walls were corroded. It was replastered, reinforced with mesh at the corners and waterproofed.
- Private Villa, Rawai — Polar White — As part of a pool renovation after an overflow leak, the tanks were waterproofed and the automatic top-up and drain channel were rebuilt.
- Private Villa, Thepkrassatri — White Halo — The balance tank and the overflow were rebuilt, and the overflow was made larger and symmetrical.
- Private Villa, Pasak — The surge tank was leaking. We rebuilt it as a new tank inside the old one.
CompletedPrivate Villa, Bang Tao — Black Granite
- Scope
- Pool renovation, new pool lights and surge tank waterproofing
- Material
- PebbleCrete Classic Black Granite · PebbleCrete Supreme Black Halo on the coping
- Applied by
- Pebble Pools
- Completed
- 2025
CompletedPrivate Villa, Rawai — Polar White
- Scope
- Leak found and fixed at the overflow; tile and render stripped, new steps, drain channel, top-up, salt chlorinator and pump, new finish
- Material
- PebbleCrete Classic Polar White
- Applied by
- Pebble Pools
- Completed
- 2026
CompletedPrivate Villa, Thepkrassatri — White Halo
- Scope
- Pool extension with a shallow ledge and air massage, a jacuzzi and seating, the old steps and seats removed and new compact steps built, a larger overflow and rebuilt balance tank, a black marble feature wall with a planter and a water curtain, a smaller reworked pump room with a salt chlorinator and a new filter, new flat lights, fibre optics and projection; refinished throughout; paths, terraces, stairs and kitchens in PebbleCrete
- Material
- PebbleCrete Supreme White Halo with mother-of-pearl accents inside · PebbleCrete Glass Raindrop on the coping, the shallow ledge, the jacuzzi and the seating · PebbleCrete Glass Nightfall Pearl on the wall beside the stairs to the roof terrace · PebbleCrete Supreme White Halo in the kitchen · PebbleCrete Classic Black Granite in the outdoor kitchen · PebbleCrete Classic Fancy Grey on the paths and terraces · rough black marble wall
- Applied by
- Pebble Pools
- Completed
- 2022
CompletedPrivate Villa, Pasak
- Scope
- New pool finish and coping, the pool system, the jacuzzi pipework and a rebuilt surge tank
- Material
- PebbleCrete Classic Aquamarine, with a dark aggregate coping
- Applied by
- Pebble Pools
- Completed
- 2025
Questions we are asked
Can a pond be waterproofed without tiling it?
Yes, provided the pond has a concrete base. For concrete ponds and tanks we use coatings that hold up in the open and can carry colour, so the waterproofing can also be the finished pond surface. A pond built on a liner cannot be waterproofed by us.
What is a tank-in-tank rebuild?
A new balance tank is formed inside a leaking old one, and in difficult cases the same approach is possible for a pool shell. The inspection shows whether the existing structure and space around it make this suitable.
Does the tank need to be emptied?
Yes. Waterproofing goes onto a clean, dry concrete surface, so the tank or pond is emptied for the work.