Water Tanks Waterproofing FAQs

Water tanks are meant to safely store water without any leakages. But here it’s not just the question of leakages. The primary problem is avoiding the growth of fungus. You’d wonder how the fungus is formed? At times, seepage and leakage from overhead and underground tanks spoil the décor. This, in turn, helps the growth of algae and fungus, which leads to weakening of the structure. For this reason, such areas should be made waterproof as well as safe for potable water. For this, you have to employ the right water tank waterproofing method using the right products—Dr Fixit Pidicrete URP & Dr Fixit Fastflex. Before using these water tank waterproofing products, make sure you keep the following things in mind:

1. Surface to be treated should be clean and free from dirt, oil and other loose material
2. Concrete or masonry surfaces should be fully cured before application
3. All surface cracks, undulations and voids must be repaired appropriately before application
4. Correctly grout all construction joints using polymer modified mortar using Dr Fixit Pidicrete URP
5. Surface to be treated with Dr Fixit Fastflex must be in a saturated surface dry condition before application​

To waterproof the water tank from inside, we recommend using Dr Fixit Pidifin 2K, an acrylic cementitious waterproof coating. For other water tank waterproofing, we suggest Dr Fixit Dampguard. The two-component epoxy waterproof coating can help protect the tank from forming algae and fungus or any additional bacterial growth.

Usually, the biggest concern with such water tanks waterproofing products is if they will affect the taste of the water as no one wants to mess with drinking water. Worry not. These products contain constituents that are entirely safe to use with drinking water. The products have been approved by CFTRI, Mysore for its potability and safety. Hence, Dr Fixit Pidifin 2K surely does work as effective water tanks waterproofing solution for new homes.

Dr. Fixit's approach to swimming pool waterproofing involves applying a waterproofing coating or cementitious system to the pool's concrete shell before tiling, ensuring the structure itself is watertight rather than relying on tile grout alone. This is especially important in India, where pools often sit close to the water table or face constant hydrostatic pressure. Cracks and construction joints need particular attention since they are common leak points, and Dr. Fixit recommends professional application to ensure the coating cures properly before the pool is filled.

Dr. Fixit waterproofing for tanks typically starts with cleaning the internal surface thoroughly, repairing any cracks or honeycombing with a crack filler, and then applying a cementitious or coating-based waterproofing system such as Dr. Fixit Pidiproof LW+ to the walls and floor. For tanks storing drinking water, it is important to use a product suitable for potable water contact and to allow the recommended curing time before filling the tank. Overhead tanks, sumps and swimming pools each have slightly different requirements, so Dr. Fixit recommends matching the product to the tank type and usage.

Dr. Fixit waterproofs underground tanks using a combination of integral compounds mixed into the concrete during construction, such as Dr. Fixit Pidicrete URP, and surface-applied coatings on the internal walls and floor for added protection. Underground tanks face continuous contact with soil moisture and groundwater pressure from outside, so waterproofing needs to withstand this ongoing exposure rather than just occasional wetting. Cracks and construction joints are common leak points and should be repaired before any coating is applied.

Dr. Fixit Pidiproof LW+ can be used as an integral compound in tank walls or as part of a surface-applied waterproofing system for overhead tanks, sealing the internal surface against leaks and cracks that develop from constant water pressure and weathering. Since overhead tanks are elevated and harder to access for repairs, using a durable, potable-water-safe waterproofing system from the start helps avoid frequent maintenance. Regular inspection for cracks or leakage at the tank's base and joints is recommended even after waterproofing is applied.

Dr. Fixit Pidiproof LW+ is an integral waterproofing compound that can be added to the concrete or plaster mix while constructing or repairing a sump tank, reducing water permeability from within the structure itself. This is particularly useful for underground sumps, where external access for repairs is difficult once the tank is buried. For added protection, a surface-applied waterproofing coating can be used on the internal walls and floor of the sump before it is filled with water, and Dr. Fixit recommends using potable-water-safe products for tanks storing drinking water.