Frequent Partial Water Changes
- Thread starter Cariogram
- Start date
Freshwater is never harmful. 30% every few days would be better though. Of course 10-15% is probably more than a lot of people that keep fish end up doing.
cyberbeer65
Scratch Glass!
I do 50% at least once a week,sometimes twice.Just make sure to use a good water conditioner like Prime.
my definition of a good water conditioner is how many gallons of water does it treat for a buck. All i have ever been after is chlorine and chloramine elimination. Along with the heavy metal detox. After that you seem to be paying for worthless marketing hype.
Fresh water will restore all the electolytes that need restoring. It will provide all the trace minerals that may have been depleted. It doesn't do anything for the aloe vera. But wait, i forgot, fish don't immerse themselves in aloe vera anyway. A healthy fish should not need anything to "restore" their slime coat. Water changes do not wash away slime coats.
And, the bacteria oriented water conditioners that suggest you need to use them at every water change--no. the colony of denitrifying bacteria in your tank does not get damaged during water changes.
DeChlor and Tap Water Conditioner are two products that bring the cost per gallon of water conditioning way down. There are others--those are just two I have used for many years.
I know a lot of people that swear by amquel. That way they are protected from the ammonia released as chloramines have the bonds broken. They are more comfortable not exposing their fish to the brief ammonia spike. I do not pay attention to that . Have never experienced any problems. And, the bio-filter will take care of the free ammonia that results from the chloramine elimination very quickly.
Fresh water will restore all the electolytes that need restoring. It will provide all the trace minerals that may have been depleted. It doesn't do anything for the aloe vera. But wait, i forgot, fish don't immerse themselves in aloe vera anyway. A healthy fish should not need anything to "restore" their slime coat. Water changes do not wash away slime coats.
And, the bacteria oriented water conditioners that suggest you need to use them at every water change--no. the colony of denitrifying bacteria in your tank does not get damaged during water changes.
DeChlor and Tap Water Conditioner are two products that bring the cost per gallon of water conditioning way down. There are others--those are just two I have used for many years.
I know a lot of people that swear by amquel. That way they are protected from the ammonia released as chloramines have the bonds broken. They are more comfortable not exposing their fish to the brief ammonia spike. I do not pay attention to that . Have never experienced any problems. And, the bio-filter will take care of the free ammonia that results from the chloramine elimination very quickly.
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do the math
You can do the math to see what this does in the tank...
fish waste = W
days = D
in one day you have 1W. 2 days you have 2W.
At the end of day 2 you remove 15% of the water in the tank, so you kept 0.85(2W) = 1.7W
Day 3 and 4 adds 2W, tank now has 3.7W and you do a 15% water change, so you kept 0.85(3.7W) = 3.145W Notice the W in the tank is still building up.
If you build a spreadsheet or do the math on paper, you will find that the Stable level (S) in the tank will stabelize at
S=D/% where % is the percent of water changed, as a decimal (15% = 0.15)
and D is the number of days until water changes (everyday D=1, everyother day D=2, every week D=7, everymonth D=30.4))
So, every other day 15% W=2/.15 = 13.3
which means this is just like having a fresh new tank full of water and not changing the water for 13 days, that is the stable level of fish waste in the tank. Probably not too bad, a fresh tank changed out completely every 2 weeks would be fine, IMO.
You can see that is mathematically equal to several other options, a 50% water change once a week is 7/.5 = 14.0 nearly the exact same result at stabelization. The only difference is that by the time of the water change, the weekly change lowers the level by a lot then lets it build to the same point, while the everyother day lets it stay at that point and drops it just a bit at water change day.
It just depends on how easy it is to do a 15% water change everyother day vs a 50% water change every week.
For anyone who has gotten this far and not just clicked on to something easier to follow, note that a 25% water change once every two months stabelizes at 61/.25 = 244 or there is 244 days worth of fish waste in the tank.
Cariogram said:
You can do the math to see what this does in the tank...
fish waste = W
days = D
in one day you have 1W. 2 days you have 2W.
At the end of day 2 you remove 15% of the water in the tank, so you kept 0.85(2W) = 1.7W
Day 3 and 4 adds 2W, tank now has 3.7W and you do a 15% water change, so you kept 0.85(3.7W) = 3.145W Notice the W in the tank is still building up.
If you build a spreadsheet or do the math on paper, you will find that the Stable level (S) in the tank will stabelize at
S=D/% where % is the percent of water changed, as a decimal (15% = 0.15)
and D is the number of days until water changes (everyday D=1, everyother day D=2, every week D=7, everymonth D=30.4))
So, every other day 15% W=2/.15 = 13.3
which means this is just like having a fresh new tank full of water and not changing the water for 13 days, that is the stable level of fish waste in the tank. Probably not too bad, a fresh tank changed out completely every 2 weeks would be fine, IMO.
You can see that is mathematically equal to several other options, a 50% water change once a week is 7/.5 = 14.0 nearly the exact same result at stabelization. The only difference is that by the time of the water change, the weekly change lowers the level by a lot then lets it build to the same point, while the everyother day lets it stay at that point and drops it just a bit at water change day.
It just depends on how easy it is to do a 15% water change everyother day vs a 50% water change every week.
For anyone who has gotten this far and not just clicked on to something easier to follow, note that a 25% water change once every two months stabelizes at 61/.25 = 244 or there is 244 days worth of fish waste in the tank.
cyberbeer65
Scratch Glass!
