If your farm is quite small, then you might assume that you would have no need for more than one rainwater tank. However, here are some reasons why you should consider getting at least one additional rainwater tank on your land.

To avoid wasting water if one rainwater tank gets damaged 

One important reason to keep a spare rainwater tank on your farm is that it could help you to avoid wasting any rainwater you've collected in your main tank if this tank gets damaged and springs a leak. Even though rain tanks are generally robust items and don't tend to develop leaks due to the deterioration of the tanks' materials, they can still get damaged by, for example, heavy farm machinery colliding with them or large farm animals knocking them over.

If an incident like this takes place on your farm when you only have one tank, and the rainwater you've been collecting in it for several weeks starts to seep out of a cracked section of it, you might then have nowhere else to transfer this water to and would need to either find an immediate use for it or accept the loss of this important resource. If however, you had a second spare tank that was empty or only half-filled, you could transfer most, if not all of the water from the cracked tank to the spare one (using buckets) and could then keep storing the water in it.

To capitalise on any unexpected, extended bouts of rain

Another reason to consider having at least one extra rainwater tank on your farm is that it could allow you to make the most of any unexpected extended bouts of rain. If you need a tank precisely because the climate in the area where your farm is situated is quite dry, you might think that having any surplus tanks would be a waste of money. However, even in somewhat dry climates, the weather can be unpredictable at times and there may be periods when it rains heavily for several days in a row. If this happens and you have one or two extra rain tanks, you could end up with many more litres of water than you would have if you only had a single rain tank available.

This could then save you the cost of watering your crops or hydrating your livestock with mains water for quite a while. Because rain tanks themselves can last for years, you could, over time, not only recoup the cost of the additional tank but could gradually make significant savings by drastically reducing your mains water consumption.