Dosing question

[mrtian97]

system is 120 gallon, I use Kalk (8 tsp for 5 gallon RODI) for ATO, and supplement manual dosing Ca, Alk and Mg (no doser yet). It's 5 months old system, have mixed LPS and SPS, zoas and soft coral. Current parameter:
Alk: 8.4
Ca: 410
Mg: 1,280
pH: 8.2

Question: I notice that my Ca fairly stable, even if I don't dose any Ca (just from my Kalk ATO), but my Alk varied quiet a bit, I noticed couple days ago was 9.3 then 2 days without dosing Alk, it went down to 8.4 (is this possible with Kalk ATO?).

Second question, I dose with Red Sea Mg, seems my level stable at 1,280 even with daily dosing, it won't increase much. Is this normal?

Thanks all

 

[Rob Lion]

You need to get your calcium and alkalinity balanced first at Ca 420, Alk 8.4 , this will make it more stable.
check the R2R calculators page/posts to see what amounts of Ca balance with what amounts of Alk

Having either Ca or Alk out of balance will affect the results on adding supplements..you otherwise end up forever chasing the numbers... as when you add Ca, Alk goes DOWN, when you add Alk, Ca goes DOWN.
Your Kalk will then add what you need and keeping it in balance as it adds equal calcium and Alk in balance.
If you are using Red Sea Foundation A and B for Ca and Alk as supplements, be careful, they have to be added in UNEQUAL measures, for the foundation B bottled liquid type dose 3.333 times what you dosed for Ca, so if you dosed 10ml Ca, your will need to dose 33.3ml of Alk. If you use the power type A and B foundations, its 6.666 times the Ca, so if you dose 10ml Ca you will need to dose 66.6ml Alk.

Once all in balance, up your Mg to 1300. With water changes you may not need to dose Mg, but test and supplement if needed.

 

[mrtian97]

Thanks for the input. I am using reef foundation A for the Ca, but switch to ME for the Alk. Just learned that the increase in Ca will reduce Alk and vice versa. I have been just adding Alk since my Ca seems at stable level. I will look into this. Everything is doing well, just wants to eventually automate the 2 parts dosing was supplement to my ATO. Should I consider upping my ATO to the maximum of 10 tsp?

 

[Rob Lion]

kalk in ATO is great, providing your daily evaporation is constant... otherwise you are going to be adding more or less Kalk into the tank depending on evaporation meaning your Ca and dKH will be up and down on any given day(s). And dont forget to stir the ATO container.
Personally. I just use dosing pumps to dose Ca and Alk, no kalkwasser in ATO, so I can keep things more stable.

 

[mrtian97]

Thanks, I thought you don't need to stirr the ATO container once the kalk is settled (I use mine about 1 wk after I mix in the kalk)

 

[Rob Lion]

pass, sorry, i'm not a kalk ATO expert, it's just what i've read somewhere at some time, that they need occasional stirring. probably depends on how often you make the mix and how long it lasts.

 

[cmcoker]

Thanks, I thought you don't need to stirr the ATO container once the kalk is settled (I use mine about 1 wk after I mix in the kalk)

You are correct.

 

[cmcoker]

system is 120 gallon, I use Kalk (8 tsp for 5 gallon RODI) for ATO, and supplement manual dosing Ca, Alk and Mg (no doser yet). It's 5 months old system, have mixed LPS and SPS, zoas and soft coral. Current parameter:
Alk: 8.4
Ca: 410
Mg: 1,280
pH: 8.2

Question: I notice that my Ca fairly stable, even if I don't dose any Ca (just from my Kalk ATO), but my Alk varied quiet a bit, I noticed couple days ago was 9.3 then 2 days without dosing Alk, it went down to 8.4 (is this possible with Kalk ATO?).

Second question, I dose with Red Sea Mg, seems my level stable at 1,280 even with daily dosing, it won't increase much. Is this normal?

Thanks all

It takes a lot magnesium supplement to actually raise the number, how much are you adding to how large of a tank?

If you haven't already, check out Randy Holmes-Farley's articles in the chemistry forum. There's a sticky with a ton of reading. Start with the article "everything your grandma never told you about kalkwasser" it's called something like that..

 

[Randy Holmes-Farley]

Alkalinity always moves around a lot faster from over or under dosing because there is so much less of it in seawater. That why it is the parameter to monitor most when dosing a balanced supplement, such as limewater or equal parts of a two part.

 

[Randy Holmes-Farley]

Thanks for the input. I am using reef foundation A for the Ca, but switch to ME for the Alk. Just learned that the increase in Ca will reduce Alk and vice versa. I have been just adding Alk since my Ca seems at stable level. I will look into this. Everything is doing well, just wants to eventually automate the 2 parts dosing was supplement to my ATO. Should I consider upping my ATO to the maximum of 10 tsp?

Don't believe claims that boosting calcium lowers alk. It really doesn't work that way to the extent some folks claim. Changing from calcium at 400 ppm to 450 ppm makes a much smaller effect on the consumption rate of alk than does a 0.1 pH unit increase in pH. So don't focus too much on that issue.

 

[horseplay]

Don't believe claims that boosting calcium lowers alk. It really doesn't work that way to the extent some folks claim. Changing from calcium at 400 ppm to 450 ppm makes a much smaller effect on the consumption rate of alk than does a 0.1 pH unit increase in pH. So don't focus too much on that issue.

I am interest in the part that the alk consumption is affected by pH. Are you saying coral growth is affected by PH if so would a higher PH (lesser co2 level) improves the growth of corals that consume alk?

 

[Randy Holmes-Farley]

My statement above is based on abiotic precipitation of calcium carbonate, which is the only likely way that raising calcium from 400 to 450 ppm will impact alk consumption, but it is true that raising pH in generally thought to raise coral calcification rates, at least for many corals.

So if growth rate is the main concern, higher alk and pH is desirable.

 

[mrtian97]

thanks Randy, my pH seems pretty stable around 8.2-8.4.
My Mg seems kept at 1240-1280 level while I would like to increase it to 1300 level but doesn't want to add too much. is this normal? I daily dose about 5-7.5 mL of Reef Foundation C

 

[horseplay]

My statement above is based on abiotic precipitation of calcium carbonate, which is the only likely way that raising calcium from 400 to 450 ppm will impact alk consumption, but it is true that raising pH in generally thought to raise coral calcification rates, at least for many corals.

So if growth rate is the main concern, higher alk and pH is desirable.

Thanks Randy. Understood.

 

[Randy Holmes-Farley]

thanks Randy, my pH seems pretty stable around 8.2-8.4.
My Mg seems kept at 1240-1280 level while I would like to increase it to 1300 level but doesn't want to add too much. is this normal? I daily dose about 5-7.5 mL of Reef Foundation C

I do not know how much is in Foundation C, but I'd just make a one time boost to 1300 ppm, and it can take a lot of any additive.