Some Questions about All For Reef

[Rybren]

Are Calc Mag and Alk depleted simultaneously at a set ratio? For example if Alk had lost x% in a day can we deduce that Calc and Mag have lost y% and z% in the same timeframe?
sorry if that’s off topic

Yes, they are. I believe that Randy has said that for every 2.8 dKH of alk consumed, 18-20ppm of Calcium is consumed. I forget the amount of Mg consumption, but it is minuscule in comparison.

 

[Randy Holmes-Farley Verified Community Expert]

Randy, in your opinion in my 32 gallon tank, if you were deciding between two part and all for reef what would you choose?

I would use a two part.

 

[Randy Holmes-Farley Verified Community Expert]

Are Calc Mag and Alk depleted simultaneously at a set ratio? For example if Alk had lost x% in a day can we deduce that Calc and Mag have lost y% and z% in the same timeframe?
sorry if that’s off topic

As Rybren mentioned, the ratio is relatively fixed for any sort of calcium carbonate formation, whether it is by corals, on heaters, or onto your sand as it hardens.

The ratio is about 2.8 dKH, 18-20 ppm calcium, and 0-2 ppm magnesium. The reason for the range is that some organisms deposit high magnesium calcite (like coralline) and it replaces some of the calcium with magnesium. Coral skeletons do that too, but to a smaller extent, and are somewhat variable on magnesium replacement of calcium. Strontium also fits into this ratio, replacing 1% of the calcium ions, but since it weighs twice as much as calcium, the consumption is about 0.4 ppm strontium per 2.8 dKH, at a normal strontium level (if strontium levels change, the amount incorporated changes too).

However, there are some other ways that alkalinity is impacted in a reef tank that may mess with the observed ratio, such as water changes, rising nitrate levels (depletes alk), dosing nitrate (adds alk when it is consumed), sulfur denitrators (deplete alk), and maybe some other even smaller effects. So when the alk demand is unusually low, any deviation from the expected ratio can get bigger.

 

[mlivvy]

I dose all for reef in my 24g and can't seem to keep my alk under 10 dKH. I've changed the dosing amount on 3 occasions which lowered the cal by 10 ppm (from 460 ppm, to 450, to now 440) but the Alk stays at 10 dKH all the time. I thought it was a dream come true for us nano owners but, it doesn't maintain the Alk where I like it. I think i'm going back to 2 part.

 

[Hydrored]

I dose all for reef in my 24g and can't seem to keep my alk under 10 dKH. I've changed the dosing amount on 3 occasions which lowered the cal by 10 ppm (from 460 ppm, to 450, to now 440) but the Alk stays at 10 dKH all the time. I thought it was a dream come true for us nano owners but, it doesn't maintain the Alk where I like it. I think i'm going back to 2 part.

What are your nutrients at? I said it somewhere in this thread that all for reef is meant to dose once you have your parameters where you want them and it takes a bit to see the dosing effects due to the bacteria needing to do its job.

 

[mlivvy]

What are your nutrients at? I said it somewhere in this thread that all for reef is meant to dose once you have your parameters where you want them and it takes a bit to see the dosing effects due to the bacteria needing to do its job.

nitrates are close to 0 and Phos is at .02.

I do use tropic marin pro salt tho which could be elevating the alk. If I stop dosing the all for reef now, the cal will drop alot.

 

[Hydrored]

nitrates are close to 0 and Phos is at .02.

I do use tropic marin pro salt tho which could be elevating the alk. If I stop dosing the all for reef now, the cal will drop alot.

I use Tropic Marin reef pro salt and it consistently test 7.4-7.6 DKH, I dose it to 8.2 DKH to match my tank before a water change. Something seems off to have a DKH that high with all for reef and using tropic Marin reef pro. I run nitrates at 4 and phosphates at .03. What are you using to test the DKH with? How much all for reef are you dosing?

 

[mlivvy]

I use Tropic Marin reef pro salt and it consistently test 7.4-7.6 DKH, I dose it to 8.2 DKH to match my tank before a water change. Something seems off to have a DKH that high with all for reef and using tropic Marin reef pro. I run nitrates at 4 and phosphates at .03. What are you using to test the DKH with? How much all for reef are you dosing?

I'm testing DKH with tropic marin. I run a brs doser for 1 minute and its putting in about 1.5 to 2 ml daily which is less than half of the recommended using the calculator.

 

[Randy Holmes-Farley Verified Community Expert]

What are your nutrients at? I said it somewhere in this thread that all for reef is meant to dose once you have your parameters where you want them and it takes a bit to see the dosing effects due to the bacteria needing to do its job.

I can't see how nutrient levels effect the calcium level at fixed alkalinity.

 

[Randy Holmes-Farley Verified Community Expert]

I use Tropic Marin reef pro salt and it consistently test 7.4-7.6 DKH, I dose it to 8.2 DKH to match my tank before a water change. Something seems off to have a DKH that high with all for reef and using tropic Marin reef pro. I run nitrates at 4 and phosphates at .03. What are you using to test the DKH with? How much all for reef are you dosing?

It just means he is dosing enough to get that alk.

 

[Hydrored]

I can't see how nutrient levels effect the calcium level at fixed alkalinity.

I agree, it more more to with the 10 DKH and the water changes. Seems high, maybe 1.5 ml is enough to raise it to 10dkh. I found when running higher nutrients it impacts the alkalinity with all for reef.

 

[Randy Holmes-Farley Verified Community Expert]

I agree, it more more to with the 10 DKH and the water changes. Seems high, maybe 1.5 ml is enough to raise it to 10dkh. I found when running higher nutrients it impacts the alkalinity with all for reef.

I still don't understand what that means. Sorry.