Alkalinity

[jdloftness]

I want to start dosing alkalinity to my tank, so I've tested the water for seven days straight. My results are:

Sun 9.7 dKH
Mon 9.5
Tue 9.4
Wed 9.1
Thu 9.1
Fri 9.0
Friday evening I performed a 10% water change with approximately a 1.026 salinity level
Sat 9.4

Let's say for discussion, I wanted to maintain a level of 9.7 dKH. How to I calculate how much to dose each day, taking into consideration the slight alkalinity spike when I perform water changes? How do you account for the depletion, but factor in water changes? Guidance and expertise is appreciated.

 

[W1ngz]

Just take your starting point, and subtract the end point, in this case, after the water change, so 9.4.

9.7-9.4 means over the week you need to make up an overall deficit of 0.3 dkh.

Whatever product you choose will have a dosage, usually telling you how many ml will raise 10 gal by a certain dkh. You can use an online calculator for your specific total water volume. http://reef.diesyst.com/chemcalc/chemcalc.html

Divide the quantity required to increase by 0.3 dkh over 7 days for your daily dosage.

For the small amount you need, it might be simpler to just dissolve a small amount of baking soda into your topoff water, in this case, 3.4g of baking soda if you have say, 100 gal of water volume. The calculator above will tell you the correct amount for your actual water volume.

 

[jdloftness]

Just take your starting point, and subtract the end point, in this case, after the water change, so 9.4.

9.7-9.4 means over the week you need to make up an overall deficit of 0.3 dkh.

Whatever product you choose will have a dosage, usually telling you how many ml will raise 10 gal by a certain dkh. You can use an online calculator for your specific total water volume. http://reef.diesyst.com/chemcalc/chemcalc.html

Divide the quantity required to increase by 0.3 dkh over 7 days for your daily dosage.

For the small amount you need, it might be simpler to just dissolve a small amount of baking soda into your topoff water, in this case, 3.4g of baking soda if you have say, 100 gal of water volume. The calculator above will tell you the correct amount for your actual water volume.

Awesome. Thank you for your advice. Regards