Water change calculator

[Mugwump]

Interesting little tool.....it'll give you some idea anyway..

http://www.hamzasreef.com/Contents/Calculators/EffectiveWaterChange.php

[PaulineMi]

Interesting to see the difference between amount removed over 2 days vs 1 month doing a 60% daily water change.

Thanks. Fun tool.

[BallAquatics]

Doesn't work for me.      Doing 50% change weekly at the end of the month says I have 93.75% NEW water.  The most I could have is the 50% I changed the last week of the month.....

I much prefer The method David Boruchowitz outlined in his 2 part series in TFH.  I think it gives a clearer indication of the amount of "junk" left in the water after water changes.  Doing a 50% change weekly the amount of crud builds up very quickly.....

Week #1
  Remove 50% pollution 50% remains

Week #2
  Remove another 50% of the original 50% so now only 25% remains from Week #1
  Remove 50% of this weeks pollution 50% remains

Week #3
  Remove another 50% of the original 25% so now only 12.5% remains from Week #1
  Remove another 50% of Week #2 original 50% so now only 25% remains from Week #2
  Remove 50% of this weeks pollution 50% remains

Week #4
  Remove another 50% of the original 12.5% so now only 6.25% remains from Week #1
  Remove another 50% of Week #2 original 25% so now only 12.5% remains from Week #2
  Remove another 50% of Week #3 original 50% so now only 25% remains from Week #3
  Remove 50% of this weeks pollution 50% remains

Using this math, at the end of the month we have 6.25% of our original contaminates from week #1, 12.5% from week #2, 25% from week #3, and 50% from this week after our weekly 50% change.  It's a good thing fish are really tough little creatures!

Dennis

[Mugwump]

Doesn't work for me.      Doing 50% change weekly at the end of the month says I have 93.75% NEW water. 
Using this math, at the end of the month we have 6.25% of our original contaminates from week #1, 12.5% from week #2, 25% from week #3, and 50% from this week after our weekly 50% change.  It's a good thing fish are really tough little creatures!

Dennis

It's the same per the calculator, but doesn't pro rate the water as it goes along....I agree tho, at the end you still have 50% of old water after this change...original water is at a minimum still tho, the words 'new water' is misleading.....the idea of water changes is to refresh what water is currently in the tank...
.....

I just went back and calculated using weekly changes and the results were about the same as what David Boruchowitz received....I guess you'd have to do it in increments to arrive at his results along the way ,using the calculator...end result is the same for 'old water' remaining but it's presented as a 'monthly' view rather than right after the last change.....semantics....LOL

[BallAquatics]

.....the words 'new water' is misleading.....the idea of water changes is to refresh what water is currently in the tank...

Agreed, I thought it was VERY misleading.  Give you that warm a fuzzy feeling that your fish are in 93.75% new and clean water by doing 50% water changes, when the reality of it is quite different....

..... in the end, I guess I'm preaching to the choir. Since most of us here are breeders and know the importance of super high quality water...  LOL   

Dennis