From: OnlineWaterproofingShop Team <[email protected]>
Sent: Monday, 23 March 2020 12:30 PM
Subject: RE: you have three small cracks just appearing in my concrete tank Team


Good Afternoon


It was good to catch up with you this morning regarding your leaking tanks

Following our discussion, I would recommend strengthening and sealing the internal walls & floor of your tank.


Leaking cracks in old water tanks are not always easy to fix using Drizoro products the method of repair depends on the whether or not the crack is flexing.


Maxseal Foundation | Maxseal Flex  | Maxrest | Maxmesh |

Maxjoint Elastic for Expansion Joints and moving cracks (most cracks will be moving in leaking tanks) The tank is flexing as the level of the water rises and falls.

The best way to repair a tank or any other retaining water structure is on the waterside

External or Outside of Tank

To stop a simple leak use Maxplug, on a crack this often moves the leak to the next weak spot. Over time the crack can reopen due to the movement as mentioned above

Please call 0466 797900 and I can discuss you’re the various options

With tank repairs, Drizoro recommends opening the crack at least 20 * 20 mm and filling with Maxrest where dry and Maxplug where wet (running water).

Then coating with 2 coats Maxseal Flex reinforced with 200 mm wide Maxmesh

maxplug-squarecut-reverse-cork-stops leaks-intantly

Internal or Inside the Tank

No matter what the age of the tank Drizoro recommends sealing the complete tank for the best protection of the tank and its longevity.

Internally you can use Maxseal Foundation or Maxseal Flex are the coatings of choice. If flexing is high then the Maxseal Flex is recommended.
Over cracks use Maxseal Flex with Maxmesh embedded in the first coat.


Where the structure is weakened we recommend that a support pillar, to spread the pressure over the crack over a larger area, be built.
This pillar can be built using Drizoro Maxrite 700 or Drizoro Maxrest

The pillar over the crack can be reinforced with reinforcement steel for extra support

Disclaimer: we are not engineers so make sure any pillar using Maxrest or Maxrite 700 is sufficient to support your tank wall/floors.

NOTE: coving over floor wall joint should be rounded (cornice) scrabble in the floor wall joint to get the best adhesion.

The size of the coving is dependent on the strength required to join the wall to the floor.

The tank can also be supported with steel bands or other methods to contain the walls of the tanks from flexing.

More reading on concrete water tanks

Reinforced Concrete Tanks Leaking Water >>> read the section about flexing structures

Thanks for visiting our waterproofing shop. Don’t hesitate to call 0466 797900 or reply to this email [email protected] address to get further information.

If you supply dimensions and size of the tank I’m happy to calculate your requirements

The diagrams below will help you understand the process. Happy waterproofing.



Ian Manson
OnlineWaterproofingShop Team
Mobile: +61 466 797 900 

Email: [email protected]

Notes and Diagrams:
Before using  Drizoro Maxplug Please watch the Video here>>


Diagram below show typical waterproofing for internal retaining structure in your case a water tank.





OnlineWaterproofingShop Team
Mobile: +61 466 797 900 

Email: [email protected]





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