Why a weekly 50% WC is better than two weekly 25% WCs

[JteSchertz]

~3ppms/day is just an assumption then....I think what jlnguyen74 and some others are stating that the data might be more proof if it were from actual data pulled from actual testing. But then again, each person's tank would be different depending on bioload. I think it is interesting to put the data out there in the format it was presented, but I find it stange that it is being quoted as an exact fact when it is based upon assumed formulas.

 

[calioutlaw1a]

So what about those running constant drip systems? What would the data look like for someone who dripped 10% a day, versus someone who did a 70% weekly water change? Same pattern?

Yes the same principle applies. Here's the actual numbers (a drip system would require an enormous number of calculations, so I'm going with 10% per day - but the data can be extrapolated for a drip system):

Adding 20ppm per week with 10% water changes per day:

• Minimum nitrate = 25.7
• Maximum nitrate = 28.5
• Average nitrate = 27.1

Adding 20ppm per week with one 70% water change per week:

• Minimum nitrate = 8.6
• Maximum nitrate = 28.5
• Average nitrate = 18.6

Again a single larger water change is better than multiple smaller water changes of the same total volume in a given time period with regards to nitrates. With daily small water changes your fish are exposed to a consistently higher level of nitrates.

You also see another important pattern here: The larger the difference in water changes, the larger the difference is in average nitrates. It was only a 5ppm difference with 2x 25%wcs vs a 50%wc, where here it's an 8.5ppm difference.

Obviously if your drip system allows you to achieve 0 nitrate then this no longer applies, but that is not the situation I'm referring to.

 

[jlnguyen74]

~3ppms/day is just an assumption then....I think what jlnguyen74 and some others are stating that the data might be more proof if it were from actual data pulled from actual testing. But then again, each person's tank would be different depending on bioload. I think it is interesting to put the data out there in the format it was presented, but I find it stange that it is being quoted as an exact fact when it is based upon assumed formulas.

Thank you!

 

[ScatMan]

~3ppms/day is just an assumption then....I think what jlnguyen74 and some others are stating that the data might be more proof if it were from actual data pulled from actual testing. But then again, each person's tank would be different depending on bioload. I think it is interesting to put the data out there in the format it was presented, but I find it stange that it is being quoted as an exact fact when it is based upon assumed formulas.

the ppms/day doesn't matter, it could be any # or even a fluctuating #. it still does not change the results.

a tank with 1 50% will have the same max ppms as 2 25% but the average will be lower in the tank with 1 50%wc. what is everyone not getting?

the formulas are not assumed, they are mathematically proven.

this might be a better way to visualize it:

take 2 cups of red water (cup a and b).

dump 50% out of cup a and replace with clear water

dump 25% out of cup b and replace with clear water

now cup a has 50% red water and cup b has 75% red water

dump 25% out of cup b again and replace with clear water

now cup a still has 50% red water but cup b only has 56.25% red water

cup b (2 x 25% wc) has dirtier water than cup a (1 x 50% wc)

 

[vfc]

deleted post

 

[ScatMan]

Thank you!

what are you thanking him for, it doesn't support what you're saying or disprove what op is saying?

 

[jlnguyen74]

what are you thanking him for, it doesn't support what you're saying or disprove what op is saying?

Unlike you, I appreciate a person with an open mind!

 

[ScatMan]

Unlike you, I appreciate a person with an open mind!

open mind about what? i've taken in to consideration things that you have not, my mind is actually more open than yours.

 

[jlnguyen74]

the ppms/day doesn't matter, it could be any # or even a fluctuating #. it still does not change the results.

a tank with 1 50% will have the same max ppms as 2 25% but the average will be lower in the tank with 1 50%wc. what is everyone not getting?

the formulas are not assumed, they are mathematically proven.

this might be a better way to visualize it:

take 2 cups of red water (cup a and b).

dump 50% out of cup a and replace with clear water

dump 25% out of cup b and replace with clear water

now cup a has 50% red water and cup b has 75% red water

dump 25% out of cup b again and replace with clear water

now cup a still has 50% red water but cup b only has 56.25% red water

cup b (2 x 25% wc) has dirtier water than cup a (1 x 50% wc)

You use red dye to compare with living organism, and you think that's a "better way to visualize it?" Red dye is constant, while fish produce waste, a variable, unknown matter...
Formula is not mathematically proven! Formula is symbol and relation. Formula has unknown variable...

open mind about what? i've taken in to consideration things that you have not, my mind is actually more open than yours.

With all due respect, it looks like your mind was way too open that your brain fell out...

 

[Dan F]