Calcium Chloride/Calcium And Alkalinity 12/12/09
I'm just learning of the problems that can arise from supplementing a reef tank continuously with Calcium Chloride....in this case Seachem's Reef Advantage Calcium.
<This product is best used short term to rapidly increase calcium levels.>
This product has worked incredibly in my smaller systems, yet now that I am 6 months into a 150 gallon sps reef, I'm noticing a few things that are entirely irregular. Firstly, my salinity has crept up to 1.028. I've always been diligent about 1.025 specific gravity water changes and freshwater top off, yet I'm not understanding fully how calcium chloride plays a role in this spike.
<Calcium will not raise specific gravity.>
Secondly, without supplementing calcium for over 3 weeks, my levels have stayed at 480 and not come down to my desired 420 level.
<Magnesium must be at the proper level (1280-1300ppm) to allow the calcium to be utilized by calcium loving inverts. Magnesium is a major element of sea water.>
All the while, alkalinity is depleting almost as fast as I can correct it; from 9dkh to 6 the next evening.
<High calcium levels can cause this drop.>
I recently purchased a calcium reactor and am ready to install it, but I'm afraid of what may happen if these levels don't stabilize. I've corrected specific gravity over a 6 day period and brought it down to 1.025, but want to be assured that I'm doing the right thing in setting up the reactor. Should I wait a while and keep dosing Seachem's reef builder alkalinity powder or set up the reactor and start dripping slowly.
<I would concentrate on getting the magnesium level up where it belongs.
Your corals will be able to absorb more calcium when the magnesium level is maintained. Is exactly why magnesium is always a part of calcium based treatments for osteoporosis, it increases bone density.>
I would never ask my LFS for help (unfortunately they're in the business of selling livestock, not saving it), and too many conflicting opinions would be bouncing off me from fellow reefers. Please help!!!
<You might want to take a look here.
http://www.wetwebmedia.com/calcalkmar.htm>
Thank you
<You're welcome. James (Salty Dog)> 

Calcium Oxide (Making Calcium Hydroxide) – 01/22/09
At work I have access to food grade Calcium Oxide CaO (lime). I believe when calcium oxide is mixed with water it is Calcium Hydroxide (Kalkwasser mix).
<<A bit oversimplified but yes, the Calcium Oxide “reacts” with the water during a process called “slaking” to form Calcium Hydroxide. The byproduct would then again be mixed with water to make the “Kalkwasser”>>
Can I use this instead of Kalkwasser?
<<Won’t be “instead of”… If you go to the trouble to slake the Calcium Oxide, then the byproduct will be Calcium Hydroxide (Kalkwasser powder)>>
I know a concern for Kalkwasser is that there could be harmful impurities in the raw material. I have the Certificate of Analysis for this Calcium Oxide so I know that this material has very low to no harmful impurities.
<<Considering most of the organisms we keep can detect values in the parts-per-million, even parts-per-billion range…having “very low” harmful impurities can be quite significant. But even so, this food-grade product is likely fine, and certainly no more of a risk than the grocery store pickling lime used by many hobbyists>>
I just wanted to get advice from an expert before I go and do a little experiment at home.
<<I’m no chemist, but the reaction of the Calcium Oxide and water will generate a lot of heat…and reportedly about double the volume of the solid material. I also do not know how violent (if at all) this reaction will be. I suggest any experimenting be done outside with very small amounts until you get a feel for the process. Be sure to wear eye and skin protection (as a “base” substance, the Calcium Oxide/Hydroxide is more damaging to your eyes than an acid!) and do research the “slaking” process before you start. And though not as readily accessible as he once was, you might also see if you can reach Randy Holmes-Farley (a reef hobbyist AND experienced chemist) over at Reef Central for his take on what you want to do>>
Thanks for your help. Love the website.
Matt
Columbus, Ohio
<<Happy to share mate. EricR…Columbia, SC>>

Calcium, calcium, where for art thou? 6/10/08
Thank you, Bob!. I read through this material last night. If I've interpreted it correctly, you recommend overall water chemistry stability, with a 350+ calcium level, more importantly than a fluctuating water chemistry due to attempting to ratchet up the calcium level? Also, use C-balance and B-ionic instead of the Purple-up?
<Ahh, yes on all counts>
(Not familiar with them so I will research what each is for and use the appropriate or both).
<Do save your time and sensibility by converting brand names to actual common chemical constituencies... you want to largely avoid Calcium Chloride... need carbonate/s, bicarbonates (yes... even that old timey Armand Hammer product can be of use...)... as well as a modicum and proportionality of Ca and Mg.>
Will also look into a calcium reactor/Kalk drip. Why not...I've got just about everything else "under the hood" at this point. lol
<Heee! A very useful tool>
I do already have a refugium with about 3 inches of a "Fiji mud" base. Currently, there is nothing in it as the red/purple Caulerpa I had in it for a long time turned into a bubble coral factory. Been trying to find a replacement, but it's been difficult.
<... Not so... I'd put at least a few to several inches of fine carbonate sand under the mud... Switch from Caulerpa to Gracilaria or Chaetomorpha... See here: http://wetwebmedia.com/refugalgfaq2.htm>
As far as a replacement adoptee for the clowns, it would seem a bad idea to place an LTA in with all of my corals. Any suggestions as to what may be a good replacement?
<Screen the Plerogyra for now and let the Premnas choose>
I know they do not need one, but if I can make them a little happier, why not?
<Indeed>
I'll be moving into a new home this December. The LFS (Aquarium Adventure or The Living Sea) both have services to move the tank. I'm going to check out your site for any hints on this moving process then see if I have any specific questions.
<Have done my share and our old co.s "Action Plan" for doing so is posted on WWM>
Thanks,
Greg
<Welcome. BobF>

Re: Calcium, calcium, where for art thou? (Follow up) 6/13/08
Hello again Bob,
<Greg>
I'm taking your advice and going to focus on developing my refugium. Currently there is about 3 inches of Fiji mud in it. The mud has been in it for 19 months and along the way housed some purple Caulerpa, green Caulerpa, and too much bubble algae. Do you recommend adding some booster mud or replacing?
<Maybe a bit more>
Right now, each of the four refugium walls is lined with green coralline algae...and a little hair algae to boot. Besides a 10 pound piece of live rock and a good number of bristle worms, it's empty.
I've alerted my LFS stores and LiveAquaria.com to email me when some Gracilaria or Chaetomorpha is available for purchase. In the mean time, I have located some Halimeda to start with. Before that, I want to add 3 inches of oolitic sand underneath the mud. This should leave me with a depth of 5 inches of saltwater? Is that too shallow?
<Mmm, not too shallow... I might raise/trade another inch of water for another of substrate though>
Am I missing anything important with regard to placing the oolitic sand under the mud?
1) Rinse the new oolitic sand with...saltwater, R/O water or tap water?
<Just tap>
2) Shut down 150 main tank water flow. I'll keep the Wavemaster running the 6 powerheads for some water movement and oxygenation in the main tank.
3) Siphon out some of the water in the refugium area so the disturbed mud will not flow into the sump area.
4) Move the mud from the left half of the refugium on top of the right half.
5) Add 3 inches of oolitic sand to the bottom of the refugium then move the mud back on top of it.
6) Repeat step 4 and 5 for the right side of the refugium.
7) Replace the 10 pound piece of live rock and add the Halimeda.
8) Let the mud settle.
9) Restart the water flow.
From reading up on WWM, I didn't see any problems with using Gracilaria, Chaetomorpha and Halimeda in tandem? I understand that a good calcium level is a must for the Halimeda.
<Likely one, two of these will be favored over the other/s... but no worries re>
Thanks so much for your help! Have a great weekend!
Greg
<Ah, thank you. Back out for a petfish pitch... This time with Frank Burr out to Phoenix. Bob Fenner>
 

Water changes in/and calcium supplements 02/19/2008
Hello,
<<Hi Tom, Andrew today>>
I have a 40 gallon reef. The stony corals I have are a frog spawn with about 10 heads, the entire specimen is somewhere between the size of a baseball and a softball. I have two Montipora caps about the size of my hand, one red, one green. I also have a Montipora digita about the size of my pinky finger. I have a aragonite sand bed that is about 3" deep. I have done a fair amount of research regarding calcium and alkalinity. I am wondering if changing 5 gallons of saltwater per week might be adequate to maintain my calcium and alkalinity levels. If not what kind of calcium supplementation method would you recommend for this size of aquarium.
<<A 10% per week water change is about an average to go for on a marine system. Of course, calcium levels are only properly known by testing your water, and buffering calcium as needed on a weekly basis, or even daily, depending on the uptake of calcium. Kent marine or Seachem calcium products should do you good service for replenishing the calcium in this tank>>
Thanks a lot, Tom
<<Thanks for the questions Tom, hope the above helps. A Nixon>>

Pickling Lime Use 10/17/07
Hello James,
First I would like to say that I'm a big fan of wetwebmedia.com Q & A. The new UV Lighting website is under construction. Our T-5 lamps have a versatile operating range that allows the lamp to run at normal wattages (e.g. F24,F39, & F54) in most fixtures & a higher wattage specifically with the IceCap ballast. Open the spec sheet attachment to see the lamp types available.
I have one question maybe you could answer for me. Have you used Mrs. Wages pickling lime for Kalk top off water? I'm trying to find a cheap quality Kalk substitute.
Thanks,
Jeremy McLellon
<<Hi Bob,
I asked for some info on T5 V-HO lamps and was asked a question about Mrs. Wages pickling lime. Any thoughts on this? See attached email below.
Regards,
James>>
<Looks good... Good to ask. BobF>
Yes, but what about the pickling lime, you know of anyone that ever used it to raise calcium. Seems like I've heard of it quite a while ago, but not sure.
Jim
<Is still widely used by some aquaculturists of biomineralizing life, and quite a few hobbyists I run into. BobF>

Calcium additions 12/8/05
Mr. Fenner, First, I'd like to say I'm a big fan, I have enjoyed reading both your Conscientious Aquarist book and articles for some time now. I currently have a 24 gallon nano cube aquarium, up until this time I have only a limited experience with dosing and do not feel very comfortable with it. However, I have begun keeping more stony corals and realize their need for sufficient calcium. 
<And Alkalinity! Calcium and alkalinity should always be added in a balanced fashion. Kalkwasser is one of the best ways. In many cases, simply using Kalkwasser to replace evaporation will meet all of the needs for calcium and alkalinity. Other options include two part additives like B-Ionic or C-Balance. Two part additives are very convenient and easy to use, but are relatively expensive. Calcium reactors are also an option, but are not practical for such small tanks.>
I would feel most comfortable with a crushed coral/aragonite substrate to provide both a buffer and calcium source for my tank, but I currently have an established tank with a thin LS substrate. 
<Crushed coral is a poor choice for many reason. Fine grained aragonite is better, but no calcific substrate will meet all of the needs for calcium and alkalinity. They simply cannot dissolve fast enough, even deep in the bed.>
I have read as much as possible but am still confused by the seemingly endless options before me. What I am considering is establishing a considerable aragonite DSB in my refugium or possibly mixing the substrate directly into my LS. Am I getting this all confused or will either of those solutions work? Sincerely, Derek Rooney Silver Spring, MD
<It is quite easy to get confused! 
While there are many benefits to DSB's (I recommend them, especially in refugia), including some modest support of Ca and Alk, they usually cannot meet all of the needs of the corals. Kalkwasser and two part additives are your best bets. Lots of information about their use is available at WWM and elsewhere on the web and better brands include excellent instructions for their use. Best Regards. AdamC.>

Calcium Supplementation in a Small Tank - 09/03/06
Hello.
<<Howdy>>
I've read in your articles that with frequent water changes supplementation of calcium, strontium, magnesium and other trace elements is not necessary in salt water tanks.
<<Many times this is true...but it is highly dependent on the amount of calcium assimilating life in the system and the frequency/volume of the water changes>>
I am thinking of slowly changing my FOWLR tank into a reef tank. Would the above still be the case in a reef tank or is supplementation required when you begin adding corals?
<<Will depend on the quantity and the species...but it is easy enough to perform water tests to determine a need for supplementation>>
Just to give you some info on my tank it is a 10 gallon with 15 lbs of live rock and 50 watts of power compact lighting.
<<Ah, I see...a tank this size rarely if ever requires supplementation as it is quite simple and inexpensive to perform adequate water changes to keep up with mineral demands>>
Thanks for your time.
<<Quite welcome.  EricR>>

High Calcium Levels 2/22/07
Hi...crew,
<Hello Mike>
I have a 54 gallon corner bow reef tank that has been up and running for about 9 months now. My problem, for which I haven't been able to find an answer to, is this. I seem to have a very high level of calcium. It's over 600 on two different test kits. Despite this high level of calcium I have very little coralline algae growth. My LFS thought I might have low levels of magnesium but I tested it and it is extremely high over 1500. Any thoughts about what's going? I'm using a RODI unit and buffering the top off water. Also, for what it's worth, my lighting is a 250w metal halide with a 20k bulb on for 12 hours a day. Thanks for taking time to read this and thanks for such an outstanding website.
<A few questions Mike.  What brand salt are you using, which brands of test kits did you test with, and, are you presently dosing calcium and magnesium?  And, for the halibut, do you read any calcium level on your RO water before mixing the salt?  James (Salty Dog)>
Mike