Alkalinity dosing

Anthrax15 · Sep 23, 2020

My tank has used 1.2 Dkh over the course of 10 days and approximately 10ppm of Calcium. How do I break it down when figuring out daily dosing? I understand WC's can take care of dosing but would prefer to have no dip in either. Do I need to dose the exact same amount for each element or close to?

Spare time · Sep 23, 2020

Test one day at x time. The next day test at the same time. If you dose during this then account for that in the math but otherwise its that simple. As for how much to dose of alk and calcium, that depends on what product you use.

Anthrax15 · Sep 23, 2020

Im more so looking for a base amount I could start dosing with. I don't want to shoot too low or too high and cause issues. I am using BRS liquid two part.

Randy Holmes-Farley · Sep 23, 2020

That is a very slow decline and you do not need to dose every day, but a fine plan is to dose about 0.1 dKH of alkalinity, and the balanced amount of calcium (about 0.7 ppm) each day. After a couple of weeks, slightly adjust it if needed.

Anthrax15 · Sep 23, 2020

Thank you very much!

blasterman · Sep 23, 2020

You say you've dropped 10ppm of calcium.

Why not 11ppm or 9ppm? My point is....very few commercially available calcium test kits have a accurate granularity of +/- 10ppm and many that say they do are lying.

My next point being calcium might not be moving at all. Alk on the other hand needs correction.

Anthrax15 · Sep 24, 2020

blasterman said:
You say you've dropped 10ppm of calcium.

Why not 11ppm or 9ppm? My point is....very few commercially available calcium test kits have a accurate granularity of +/- 10ppm and many that say they do are lying.

My next point being calcium might not be moving at all. Alk on the other hand needs correction.

Im going off of what my Red Sea Calcium kit is saying and Hanna for Alk. With that being said, I should just be dosing a very small amount of Alkalinity for now? I'd prefer to not leave it up to water changes for keeping parameters stable.

homer1475 · Sep 24, 2020

blasterman said:
My next point being calcium might not be moving at all. Alk on the other hand needs correction.

You do know this is actually impossible, right? Alk and Cal get used in a balanced ratio(roughly 18 to 20PPM per 1DKH of alkalinity). It's just our test kits cannot register that low of a drop in CAL. There is a reason people dose calcium based on alkalinity measurements.

Randy Holmes-Farley · Sep 24, 2020

Anthrax15 said:
Im going off of what my Red Sea Calcium kit is saying and Hanna for Alk. With that being said, I should just be dosing a very small amount of Alkalinity for now? I'd prefer to not leave it up to water changes for keeping parameters stable.

Dose the calcium and alk as I suggested. if you find either is too much or too little after a LONG time (weeks) then adjust.