I have absolutely no problem with people posting relevant links on appropriate pages.

I have created a rainwater tank page. If you want to add a link to your calculator, feel free to add it to the "External Links & References" section.

The output of this process is a series of graphs and other information which shows the ongoing water balances over a period of time. A second aspect of this is that it allows the complication of water restrictions to be factored in. TankSmart is 'written' in MSExcel and comes with a comprehensive manual to describe how it is to be used.

TankSmart is freely downloadable from an Australian website. Since I am not allowed to post a link in this forum if you search for a Australian professional electrical engineer called Kerry Nufer on Google, and follow the 'download' page link on his default web page, you can download the application and manual free of charge.

Kerry Nufer

Balance Tank - Is a reservoir in which the water level will vary to faciltiate balancing of water. The balancing of water is required to allow for diurnal variance. Examples: Keep water turning over in the reservior or to allow for continuity of operations at a treatment plant by allowing sufficient balancing volume in the balance tank for operations during low consumption.

Service Reservoir - Is a reservoir that maintains a full level of treated water at all times. The water level will only vary over a small range due to pumping control levels. The function is maximium reservoir storage.

I'm not 100% sure. We (Bundaberg) used distinguish between Reservoirs and Balance Tanks, but about 2 years ago we did a review of our Water & Wastewater asset names we renamed the balance tanks reservoirs.

The article below (which also mentions service reservoirs) …

http://nptel.iitm.ac.in/courses/Webcourse-contents/IIT-KANPUR/wasteWater/Lecture%2014.htm

… defines a Balancing Storage as the quantity of water required to be stored in the reservoir for equalising or balancing fluctuating demand against constant supply is known as the balancing storage (or equalising or operating storage).

So perhaps a balance tank is a reservoir used primarily to house a balancing storage?

In any case I will have a word with someone at work tomorrow who is a bit more expert in the field and see if I can get them to add an article and an authoritative definition.