- Tank Hole to be 100mm to 300mm bigger than tank on sides and 300mm lower than tank at bottom.
- A 1:6 river sand/cement mix (dry mix – Slightly Moist) is required to cover at least 300mm across the base of the excavated hole. Make sure no solid objects are protruding from cement sand dry mix.
- Insert the RotoTank septic tank into the excavated hole and bed the RotoTank septic tank properly, by gently rocking the RotoTank septic tank backwards and forwards in the cement mix, making sure the RotoTank septic tank is accurately levelled.
- Positioning of Tank – Ideal is that tank lid ends slightly lower than ground level. Ground can be slightly levelled upwards from outside towards lid as to make space for RotoTank Manhole cover.
JOINING
- When joining pipes to the Septic tank manhole, it is easily done by using water soap mix and ramming the required pipes home.
- All pipes joined to tank must have amount of flexibility. (Tank must be able to “move or breath” since cold and hot as well as full and empty does make a difference in measurement or movement of tank)
NOTE: if tank is installed lower than ground level (100mm maximum) provision must be made for a slab or lintels across the top of the tank. Remember – the tank is LLDPE plastic and can only carry so much weight and therefore must be supported.
BACKFILLING
- Fill RotoTank septic tank with water!
- A 1:6 concrete/sand mix should be carried out in 300mm thick layers from the base
- up to 100mm below the top of the septic tank manhole with the concrete filled lid
- in place on the manhole. The backfill should preferably be slightly moist.
- Each 300mm layer should be manually densely compacted to achieve 90% of modified ASH to maximum dry density.
- For excavated holes deeper than 2 150mm backfill material must consist of a soil Crete mix of 5% cement and 95% selected granular material. Cavity and Sealing is NBB.
- Contact RotoTank Technical team for High Water table Problems.
WORKING OF THE SEPTIC TANK
- Secondary – Inspection / Soak-Away / Drain Field tank is a Green Drop status Action – Access and Inspection is done with ease
- Second tank allows grey water to pass Septic tank and be disposed in Drain field.
- This tank allows for reusing of grey water in Garden or Toilet – Green Drop Status water
- Activation of the Organisms inside tank and system can be done by using an activator – available at ROTOTANK
HOW DO I CONNECT THE SEPTIC TANK?
- Connect the toilet outlet to the RotoTank septic tank inlet with a 110mm PVC pipe.
- Connect the overflow or outlet to the Soak-Away / French Drain. Making sure that Drain System it is not too close.
HOW DOES THE SEPTIC TANK INSTALLATION WORK?
- When you flush the toilet, the water and the solids collect in the RotoTank septic tank, therefore any solid waste products will float on the water.
- The bacteria from the activator will dissolve the solid waste products and produce almost clear water which settles at the bottom of the tank, which then flows out of the overflow and into the French drain.
- RotoTank Technical for – Drain Field / French Drain / Soak Away – Technical advice
Please Note:
- No sanitary towels, cigarette butts, chemical and or household cleaning products should be in the tank as it eliminates the bacteria, and the consequences are that the chemical process will not be able to take place.