Appropriate Calcium Levels

[Folta]

Up until about two weeks ago, for a period of about a month and a half, I had really good sps growth rates. Then it started dwindling. At this time, my calcium test (salifert) came in, and I checked the calcium level. It was @ ~ 270.

 

I bought some kalk, and have been dosing that into the tank with the top off water. After a week and a half of this, I checked kalk levels, and it was @ ~ 300.

 

I mixed up some new saltwater for a water change today, and took a calc reading on this mix (after its been stirring a few hours to be completely disolved). It's calc level was only around 350.

 

I was expecting it to be a little bit higher than that. What level should I am for to keep the calc at? I have about 10 small sps pieces right now, and plan to add more with the 180. I'd like to get a good growth rate (of course). I have not yet added any kalkwasser to the saltwater I plan to put in for the water change. Should I?

 

My tank specs:

 

Temp - 81 degrees

Ph 8.3

Salinity 1.025

Alk 8.0

Calcium 300

[dhoch]

Others will no doubt chime in, but for myself I target ~410-430 range...(with alk around 9.6-10.0)... this keeps them in balance.

 

If your alk is truely 8 and your calcium you need to get calcium up... kalk is a balanced addative, you will want to add straight calcium product (i.e. turbo calcium... mix with RO/DI water and add slowly over a period of time to raise calcium up).

 

You are probably using IO as water change water, which is know to have calcium levels in the 350 range.

 

Dave

[Caribbean Jake]

Limewater and kalkwasser (KW) are one and the same; a very strong calcium saturated liquid solution that is added to reef tanks to replenish the calcium absorbed from the water by many marine organisms.

 

Calcium is one of THE most essential elements in nature required by corals, crustaceans, mollusks, coraline algae and certain other calcareous forms of macroalgae to grow. By extracting calcium from sea water, they use it to build their skeletal structures from calcium carbonate. Now, this is where alkalinity comes into play. Calcium alone is not enough, because the availability of carbonate mostly depends upon pH and alkalinity. Skeletal growth can still take place if alkalinity is high, and the calcium concentration is much lower than that of sea water.

 

However, if both are low, these calcareous animals and plants do very poorly and little growth occurs. The bottom line is that calcium, carbonate, pH and alkalinity all relate to one another. To attain a thriving reef community, all of these elements apply, not just calcium by itself.. I keep my CA between 420 & 460.

 

Hope this helps.

Jacob

 

P.D.

Howard - I made my 1500 post.

Lee - the 1500 post was a quality one rather than a quantity one.

:D

[Guest Leishman]

Here is a tool to help you get your levels in-line.

 

Reef dosing calculator

[Folta]

Thanks for the links and info guys. I'm going to try to push my calcium up to 400 and my alkalinity up to 10 dkH. Looking into the tank today, I think the kalk is having a positive effect - the montiporas in particular are starting to show growth once again (the ends are becoming whiter). They typically are the first to show growth. Also the tort looks like its doing quite well... we'll see how things are when I get the levels up.

[Caribbean Jake]

FOLTA

don't rush the CA level. Good thing happen slow in reeftanks, bad things happen fast. Advise: add the CA little by little until you reach your desired level. Although most corals and animals in your tank will love the overflow of CA, it is safe to do it on a meassured matter rather than jumping from 200 to 450 all at once.

[Guest Yomeister66]

Here's an excellent article on the topic:

 

http://www.advancedaquarist.com/issues/nov2002/chem.htm

 

Also, if you have to do any kind of conversions to get your alkalinity reading (As I do with my Lamotte kit), this link might come in handy:

 

http://www.aquaticsbydesign.com/abd_calcs.htm

 

(It's halfway down the page, under "carbonate hardness converter")

[Lee Stearns]

That is a neat calculator- I had to bookmark it.

[flowerseller]

Using Turbo calcium is the best way to raise your CA however, raisng calcium often comes at the expense of ALK.

Safer to have lower CA with higher ALK than to have higher CA with lower ALK.

Test, add, wait several hours, re-test.

[steveoutlaw]

Ok, so I have a 26g with a 5g hang on fuge. What should my CA and ALK levels be? I currently have 4 SPS and some LPS in the tank.

[Lee Stearns]

when in doubt it is hard not to listen to Raandy the RC Chem guru:

ALK

2.5 - 4 meq/L or 7 - 11 dKH or 125 - 200 ppm CaCO3 equivalents

 

Calcium:

 

380

[Ne0eN]

Using the reef dosing calculator, it appears that I need 37.1 gal of Kalk to bring the Ca to 400 level. Current params:

 

Total Volume ~ 300gal

Temp: 78.5F

pH: 8.05

Ca: 300 ppm

Alk: 5.1 dKH or 1.83 meq/L

 

How fast should I be dripping Kalk? I usually mix 1 gal and drip it overnite every couple of days (haven't noticed any impact as of yet). Can I go up to 2 gal per night so that it takes 19 days vs. 37 days? Any other ideas? I'm just starting adding SPS frags, so there is no Calcium load in the system yet.

 

-Rob

[Caribbean Jake]

make sure you do it while the lights are OFF, or else your PH may pick and bring harm to your livesotck.

Jacob

[Guest Leishman]

use a 2 part solution like b-ionic to get your levels up, then use kalk to help maintain them. Kalk alone will take forever. Add as much b-ionic as you can w/o letting the Ph move more than 0.2 Make sure you add it in a high flow area and add the alk part slowly so it won't precipitate out.

[Ne0eN]

Is b-ionic available locally, or through mail order only?

 

-Rob

[Guest Yomeister66]

Is b-ionic available locally, or through mail order only?

 

-Rob

48553[/snapback]

 

You should have no problem getting B-ionic at your LFS.

[Lee Stearns]

Kakl is normally used at a rate equivalent to your evaporation rate per day- If your system is evaporating a gallon a day that is the kalk drip you want to run back in because the kalk is mixed up with fresh RO/DI it keeps your salinity constant as well. Most folks drip 24/7 and this can be done with some very simple gravity rigs, or more complex pumped setups- Chip(Flowerseller) would add that it is important to mix the kalk in some form of reactor with as little exposure to ambient air as possible- because of the CO2 in the air will form a crust on the water which is shards of calcium carbonate that will not disolve. A simple 2 liter water bottle drip system can accomplish all of this.