Round or Slimline Tanks?

These days many states require you to have rainwater storage , unless you have access to recyled water.

But which type of tank will be best?

Round Tanks

The standard is round tanks.

These cost less because they are easier to make and use less material per litre of stored water.

It is easy to see the entire contents of the tank from the top access so you can check on sediment level.

Also, it is easy to hose sediment to the tanks drain point when the tank needs cleaning. . . . NEVER GET INSIDE YOUR TANK.

Slimline Tanks

A popular shape is the slimline tank which will fit in a narrow space.

I have even seen a row of them used as a boundary fence.

A disadvantage is it is much more difficult to to clean out sediment.

Before you make a choice it could be worth thinking about finding out if you can find room for a round tank.


Typically the cost increase for a slimline tank over a round tank of the same volume is at least 50%.

A comparison from my local builders merchants:

    • $1,200 for a Slimline 3,000 Litre tank
    • $800 for a Round 3,000 Litre tank

If you haven’t the width to fit a 3000L tank you could perhaps look at getting two round 2,000Litre tanks for a similar price as the 3,000Litre Slimline tank.



See this post to find out How Much Rainwater Storage You Need