Science/Chemistry question:

Wayne Sallee wrote:
I don't think so.

Assuming: "1/2 cup of salt per gallon of salt water rule of thumb".

Assuming: 30 gallons of salt water made up to regular strength using the
"1/2 cup rule" as being the standard for the test.

Assuming: 30 gallons of regular strength water having to be taken out
for a standard water change.

Assuming: a tank size of 60 gallons.

Now for the test tank Assumptions ###########

Assuming: 5 gallons of evaporation.

Assuming: 27.5 gallons of extra salty water taken out of the tank. After
evaporation, your tank now holds 55 gallons of water, and a 50% water
change is 27.5 gallons. This 27.5 gallons of strong water is equivalent
to 30 gallons of normal strength water.


There in lies the flaw in your logic. One would not be taking out 27.5 -
one would still be taking out 30.

Therefore, one would be removing more phosphate, nitrate, etc.