Water Change Calculator

Here's a little something I put together one rainy afternoon about how much 'old' water is left after a number of water changes. i.e. Two 50% water changes doesn't equal 100% of the water changed as the second of the water changes includes some of the previous 'new' water. So two 50% water changes leaves 25% of the water unchanged.

The Table attached has a highlighted square to aid an explanation. 

The number of water changes is Column A; in this case 4

The percentage of water changed is in Row 1; in this case 25%

So if you do four 25% water changes then there is still 32% of 'old' water left in the tank.

This may be of some interest to people..... but it whiled away my coffee break.... so I'm happy! <-- See?

Row 2 is 100%. In Excel that row is changeable to the actual tank volume and the table recalculates everything into litres. But as that won't work as a posted reference I put 100litres in so the table works as a percentage figure.

I'm afraid you'll have to do the maths yourself...... or you could tell me your tank volume and I'll post a table specific for your set-up so all the figures are in litres.

Hey look..... a fishy thing to add to the post....

No probs - I'll do it at my next coffee break...... which is very soon. I drink a lot of coffee

Thanks Colin!!

 

FC

At the time I posted this it was really what I said it was, honest . It still is, but you should waft it through a virus scan before you open it!