A question about water pressure tanks ...

Simon & Nicky

Feb 3, 2004
OK boffins.. Can anyone help me? My pressure tank for my water is massive and has only lasted about three years. It stands about five feet tall and 2 feet wide and I bought it as a replacement for the one that was already installed. It now has a constant drip, drip leak coming from a rusting seam that will only get worse. I tried getting the first one patched and the fix lasted about two months but it took half a day just to get the damned thing in and out of the pool house. I don't want to ever have to do that job again so it appears that I have no choice, I need to buy a new one but prices are a bit on the high side for something so big that only lasts such a short time. I have seen a make called Well Mate that is fibreglass and will obviously last longer but nobody stocks one in such a large size. Here's the question:

Is there a formula for fitting the right sized tank for the job? If not then how small a tank (obviously much cheaper) can I get away with for a two storey house with four bathrooms. I assume that as the tank gets smaller then maybe the pump works harder and consequently your electricity bills rise but then again maybe the pressure drops just as quickly regardless.

Perhaps someone out there in DR1 land had one that was considered too small and they were told to buy a bigger one to address pressure problems?

I have to admit - I'm baffled......



Feb 3, 2002
OK, I'm no engineer either, but I had a similar issue whereas my first tank I installed was very large and it only lasted a couple of years. I asked the plumbers and I couldn't get a straight answer from anyone as to what size tank you really need (My house is 6 bedrooms, 4 baths), so I went for the smaller fiber glass and it seems to work fine for us. I don't really get the concept of the need for a larger tank as the pump once it starts is generating the pressure not the tank itself or am I wrong there?