When you choose a Promax ENDURO Water Tank, you are choosing quality and style. These ultra strong tanks are engineered to last and complement every landscape with their contemporary look. Our premium corrugated ENDURO water tanks are designed for optimum performance over many years. Here is what stands behind that claim, reason by reason.
One-piece construction
ENDURO tanks are built as a single piece, which reduces maintenance and costs and comes with the peace of mind of a 20 Year Promax Warranty. The logic is straightforward. A tank made in one piece has no seams or joins built into its walls, and a join is a thing that has to be made, checked and maintained. Removing them removes a category of upkeep rather than merely reducing it. That is also why the warranty can run as long as it does: the company offering it is not underwriting a construction method with a known weak point built into every unit it sells.
Corrugated sidewalls and burial to one metre
The corrugated sidewalls are there for superior strength and toughness, not for looks, though they deliver the contemporary appearance as well. Corrugating a wall stiffens it against the loads that try to deform it, which is the same reason the profile turns up anywhere a thin wall has to resist pressure. It matters here for a specific reason: it allows ENDURO tanks to be buried up to 1 m and still retain their 20 year warranty. That is a genuinely useful metre. It lets you drop a large tank below a sight line, or work with a sloping site instead of against it, without moving to a different product or forfeiting the cover.
The 20 year warranty and what it covers
A 20 year warranty is worth reading carefully rather than just noting. Two things about the Promax version are worth drawing out. It applies to the one-piece construction, and it survives burial to 1 m rather than being voided by it. Warranties commonly lapse the moment a tank is installed in a way the manufacturer did not anticipate, and partial burial is exactly the sort of thing that ends cover elsewhere. Here it is stated as within scope. When you compare tanks on warranty length, compare on what the warranty still covers once the tank is installed the way you actually intend to install it.
Water quality and UV stability
All Promax tanks comply with Australia and New Zealand potable water standards, which is the relevant benchmark if anyone will be drinking from the tank. The ENDURO stores clean, fresh, untainted water for drinking and household use with no tainted taste, and it is fully UV stabilised. That last point deserves more attention than it usually gets. A water tank is an object that sits outdoors, in New Zealand sun, for decades. UV is the load it is under every single day of its life, unlike the loads that only arrive occasionally, and a tank that is not stabilised against it is on a clock from the day it is installed.
Fittings and access
Each ENDURO comes with four plumbing inlet and outlet panels, a large 600 mm manhole with lid, and one 50 mm female threaded BSP outlet. Four panels rather than one is a practical decision that pays off at install time, because it lets the plumber bring pipework in from the side that suits the site rather than the side the tank happened to be craned in facing. The manhole matters for the whole life of the tank after that. Inspection and cleaning are only ever going to happen if there is a sensible way in, and a 600 mm opening with a lid is that way in.
Seven colours
The range comes in seven colours to suit your surroundings. This sounds like the least technical item on the list, and it is the one people live with most directly. A large tank is a permanent, visible object on a property, and colour is what decides whether it reads as infrastructure parked on the lawn or simply recedes into the fence line, the bush or the building behind it. Seven options is enough to actually match something rather than settle for the closest available. Given the tank is expected to last decades, choosing a colour you can live with is not a trivial decision.
Delivery
Quick and efficient arrangements are made to best suit your delivery requirements, and 10,000, 25,000 and 30,000 litre tanks are delivered free to your property. Free delivery on the three largest sizes is worth more than it appears in a specification list. Large tanks are an awkward freight problem, and the cost of getting one to a rural or difficult site is easy to leave out when you are comparing purchase prices side by side. Removing it from the equation on exactly the sizes where it bites hardest changes the real comparison, not just the advertised one.
Buying an ENDURO
All Promax tanks can be purchased through your local reseller. Before you commit, two things are worth settling. Size is the first, and our guide on what size water tank you need works through the calculation properly. The base is the second, and it is the one most often underestimated, since a tank is only as sound as what it stands on, which our advice on selecting the best base covers. If you are weighing ENDURO against the other Promax range, our ENDURO versus XPRESS comparison sets out the differences.
Where ENDURO sits in the range
The Promax ENDURO Water Tank range is, in our view, the best water tank range in New Zealand. That is our position as the manufacturer, and the specifics above are what we rest it on: one-piece construction, corrugated sidewalls, burial to 1 m inside a 20 year warranty, potable compliance, full UV stabilisation and seven colours. If the question behind your search is really about polyethylene as a material rather than this range in particular, our article on whether poly water tanks are safe addresses it directly. Browse the full water tank range to see the sizes available.