Please visit our Sponsors
FAQs on Calcium, Supplements involving Calcium, Supplements

Related Articles: CalciumThe Use of Kalkwasser by Russell Schultz, Understanding Calcium & Alkalinity, Live Sand, Marine SubstratesReef Systems, Refugiums

Related FAQs: Calcium, FAQs 1Calcium, FAQs 2Calcium FAQs 3, Calcium FAQs 4, Calcium FAQs 5, Calcium FAQs 6, Calcium FAQs 7, & FAQs on Calcium: Rationale/Use, Calcium Measuring/Test Kits, Sources of Calcium, Dosing, Chemical/Physical Interactions, Troubleshooting/Fixing, & Calcium and Alkalinity, Calcium Reactors, & Calcium Reactors, & FAQs on Calcium Reactors: Rationale/Use, Selection, Installation, Operation, Media, Measuring, Trouble-Shooting, By Makes/Models, & Kalkwasser& FAQs on: The Science of Calcium & Alkalinity, Importance, Measure, Sources, Use of AdditivesTroubleshooting/Fixing, Products,

The best? Mmm, in order... Maybe frequent partial water changes, Calcium reactors of various designs, Powdered/soluble Calcium, two part supplements or Kalkwasser for some, Calcium chloride for short term, Calcium gluconate for only supplementing for coralline algal growth. All need to be administered with awareness of alkalinity and Magnesium levels present and the use of the Calcium and Alk. by the life present...

Carib sea Aragamilk, Aragamite "Calcium", carbonate, bicarbonate... not very soluble
Kent Marine "Pro-Buffer dKH" deionized water containing carbonate, bicarbonate, sulfate and borate salts with trace minerals
Kent Marine "Liquid Reactor... Calcium" RO/DI water, chloride-free calcium, magnesium, and strontium salts from natural sources
Kent Marine "SuperBuffer dKH" carbonate, bicarbonate and borate salts of sodium, magnesium, and potassium
Kent Marine "Coral Builder" Contains carbonate, and bicarbonate salts
Kent Marine "Tech· CB parts A & B " Part A: deionized water containing the following ions: calcium, chloride, magnesium, strontium, bromide, lithium, rubidium, nickel, chromium, zinc, copper, cesium, iron, manganese, cobalt. Part B: deionized water containing the following ions: sodium, potassium, bicarbonate, carbonate, borate, fluoride, iodide, molybdate, selenate, vanadate, and tungstate
Seachem's "Reef Calcium" Calcium gluconate (sugar calcium)
Seachem's "Reef Complete" liquid calcium chloride , magnesium and strontium
Seachem's "Reef Advantage Calcium"  Calcium, magnesium and strontium
Seachem's "Kalkwasser" Calcium Hydroxide

Dosing Ca and KH       7/19/16
Thank you for taking this email.
I have a 110g reef tank of 3 months. Which is about my level of expertise, sorry. The tank has done well with many frags of coral, some fairly large.
A good number of inverts and a few fish. I use the Apex Dos system to do five 1g water changes per week. 2 days to get the replenishment tank filled and dialed in with salinity and temp. I currently dose Ca and KH manually every other day.
<Good. Am a fan of SeaChem's Fusion products, but Bob Starks, Sprung's copies C-Bal will do>
I maintain at the bottom of the spectrum...9/360. I am trying to work it up slowly,
<Also bueno>
I got behind do to ignorance. All other levels Ammonia,Nitrate,Nitrite, PH are 0. I average ph 8.3, temp 76, salinity 1.022-1.024.
<Mmm; I'd raise this to 1.025-6>
I may eventually buy another Dos, but in the meantime....could I dose up the levels of my replenishment tank(currently using Instant Ocean Reef Crystals which keep levels at 11/390) to the upper edges of the spectrum, say 12/420?
Given that depletion rate in the tank might bring it back to mid levels.
Sorry if this is a dumb question.
Ken Birgfeld
<Welcome. Bob Fenner>

Kalkwasser Help, source, commercial chemical      8/20/13
Hello Crew,
I'm trying to make Kalkwasser for a balanced calcium supplementation in my tank. I'm hoping to go the economical route by purchasing 50lbs for $8 rather than the 4.4 lbs for $50 at my lfs!
<Ah yes>
I've attached the MSDS for this product. It contains 92-100% Ca(OH)2 along with some silica. I'm wondering
if you think this will be sufficiently pure for my tank.
<Mmm; the stated range of Si is 0.1-1 % by weight, the remainder "inert"  ingredient/s most likely water... This is "not too much silica/te for me.
There may be folks who decry such non-reagent or higher grade Kalk for aquarium use... Have seen this sort of quality used by very large facilities. My spiel: no worries>
Thanks for your help!
<Welcome. Bob Fenner>

RMF not awake enough to repro. just part of the .pdf
Just looked up their MSDS online: http://www.graymont.com/msds/msds_high_calcium_hydrated_lime.pdf

re: Kalkwasser Help, comm. product; good enough?     8/22/13
Hi Bob,
As a follow up to the e-mail below I've attached a more detailed chemical analysis of the hydrated lime. Please let me know if you have any concerns about the composition.
<I (still) do not. BobF>

Sorry re... GIGO

Calcium Carbonator / Algae Growth   10/17/12
Hi.  Any opinions on Calcium Carbonator by Reef Results Marine (http://www.calciumcarbonator.com )?
<Mmm... don't like mis-use of the term "natural" in their ads, nor the lack of detail concerning the ingredients, and not a fan of one part solutions for providing alkaline earth (this one only Ca) and alkalinity to captive systems. Not sufficient control. Am a much bigger fan of proven two (or more) part solutions for providing same, calcium reactors (w/ appropriate media)...>
 The guy at the LFS pushed it when I was there about 3 weeks ago to pick up some calcium.  Since then I've had MAJOR algal blooms that I can't seem to get on top of.
<Uhh, I'd switch back to previous SOP>
 I haven't found much credible discussion about the product online, so I'm not sure if its the culprit or just coincidence.
<Me neither, given the stated data, but... would still revert. Bob Fenner>

Feel like a beginner! SeaChem Ca products    4/6/12
Hello  "most knowledgeable ones in the entire world about reefs" people!
<Wow!  Hello Pam>
At present, my tank is 2 months old and I find I'm struggling with many of the same issues that plagued me 10 years ago.
I guess the knowledge I attained then, has seeped from my brain and I find myself learning all over again.
<The technology has changed tremendously as well.>
I found an old document I used 10 years ago and was wondering if it still stands true.
As I stated in one letter, I took about 6 years off from the hobby and now I feel like a beginner!
<Mmm, the chart does not state which size tank this dosage is for.  The calcium does not have to be put into a pail and mixed.  I mix the required calcium dose with tank water in a small plastic wide mouth bottle  and slowly add to the system.  Same goes for Reef Builder.>
<You're welcome.  James (Salty Dog)>

For the health of your corals and over all environment.

Reef Plus Use 2 tablespoons EACH of

Reef Complete these products, 2 times a week.

Reef Calcium Dump directly into tank.


Reef Advantage Calcium

Reef Builder

Fill a 5 gallon pail with plain water no salt!

Week 1 >> put 1 T. Reef Advantage Calcium in pail. Use this water to top off for the first week.

Week 2 >> put 1 T. Reef Builder into ANOTHER bucket and use this for top off for the second week.

Practice this procedure forever for healthy corals!________________________________________________

Water changes should be done at the rate of about 10% a month. Only at this time do you add salt to the tank.

Calcium Chloride (Chloride Buildup?) -- 02/27/11
Dear Crew,
<<Hey Dan>>
I have been dosing 2 part solution with calcium chloride and soda ash. I get my chemicals from BRS and so far have been satisfied with the results.
<<I often obtain bulk supplements from there as well>>
I have been reading on your site that long term use with calcium chloride is not recommended.
However I could not find a reason why. Someone told me that it is the buildup of chloride ions,
but they could not tell me what it was that the chloride ions did to your tank chemistry. Could you please explain why dosing with calcium chloride is bad?
<<A valid question'¦ I can give you my simple thoughts on it, and if I stray, hopefully Bob will chime in'¦ From what I have read, the chloride ions we add to our systems (Calcium, Magnesium, Strontium, et al) are basically neutral (6.7-7.3) on the pH scale. It's thought that a buildup of these ions, overtime, can cause a skew in water chemistry making it difficult to maintain alkalinity at NSW levels (old tank syndrome?). In a system heavily dosed with these ions, it's likely that even regular water changes won't 'keep up''¦allowing the eventual buildup to a point where it mal-affects the balance of water chemistry. But I think for most hobbyists a regimen of regular monthly 20% water changes will reduce or even eliminate any concern re this buildup. And even a heavily dosed system can probably be maintained with the occasional large (50%+) water change'¦though much really depends on the usage rate of such supplements. The 'chloride' based supplements have a purpose in the hobby in my opinion (higher ratios, more easily metabolized), but understanding what you are adding and what it is doing to your system is key>>
Thanks in advance,
<<Hope this makes some sense'¦happy to share. EricR>> 
Re: Calcium Chloride (Chloride Buildup?) -- 02/28/11

Thank-you for the info, its much appreciated.
<<Quite welcome>>
So it sounds like the buildup of chloride ion will cause CaCO3 to precipitate out of solution.
<<Mmm, not that so much'¦at least no more than an 'over abundance' of any other calcium ion would. I think the issue is that when the calcium is provided as 'chloride' ions, it works against the system buffers' ability to neutralize acids, and thus affects the ability to raise/maintain system alkalinity>>
Can you recommend another form of Ca dosing that I could use instead of CaCl2?
<<You can use the Calcium Chloride products with the proper knowledge/observation/maintenance of your system as already discussed, but my preferred methods of continuous Ca dosing is through the use of a good Calcium reactor'¦and a Kalkwasser reactor. Though one needs to be aware that these methods also have their own inherent dangers from misuse/abuse and do also need to be fully understood before implementing>>
Thanks again,
<<Is a pleasure to share'¦ EricR>>Calcium Addition Clarification 1/25/11
Dear Crew,
Again, thanks so much for your deep passion for aquatic life! I truly admire your dedication to the hobby as well as to helping others. It's tough to top that!
<We thank you for your kind words.>
I've been researching calcium dosing quite a bit and came up with a few questions that you may be able to answer.
I have dosed B-Ionic 2 part calcium supplements for my mainly LPS reef in the past and have had great results with coraline algae and moderate results with coral growth.
<I'm not a fan of the two part dosing, tried it once, wasn't happy with it.>
I also have (but have not used) Seachem's Reef Advantage Calcium (calcium chloride in powder form, I believe).
< Reef Advantage Calcium is an ionic calcium that is very concentrated and very economical. It also contains strontium and magnesium ratios proportional to typical depletion rates. Unfortunately, Seachem doesn't state whether Reef Advantage Calcium is in fact calcium chloride but I'd bet my money that it is. Reef Calcium is an organic calcium complex that is very readily available. The calcium in this product is very available and your corals do not have to expend as much energy to use this form of calcium. If you intend to use Seachem's products, I'd use Reef Calcium as your primary source of calcium and only use Reef Advantage Calcium as a secondary source to rapidly bring calcium levels up if needed.>
I have been reading about uses of calcium chloride and see that many suggest only using it in the short term for quickly boosting calcium levels, not as a main source.
Upon reading the ingredients of the B-ionic, surprise surprise- it is calcium chloride. Do you think that using B-Ionic as a main supplement would have the negative effects that that are associated with calcium chloride?
<Long term use, yes.>
I am currently dosing calcium hydroxide as an alternative. This is much more labor intensive, but from my research, should provide a more suitable form of calcium.
<Yes, but as you mention, a pain to use. I've been using Tropic Marin AlkaBalance and really
like the product. It maintains both calcium and dKH and is not calcium chloride based.>
My last question involves adding C02: I have been adding 12mg of white vinegar (per quart) to the RO water prior to adding a half teaspoon of calcium hydroxide following by shaking vigorously in the sealed bucket. I read on this
site http://www.reefscapes.net/articles/breefcase/kalkwasser.html that you should dissolve the calcium hydroxide in the vinegar first, followed by diluting with RO water. In your opinion, would the order of these steps make a difference or will simply adding a source of C02 at any stage produce the desired
result of releasing more CA ions.
<I'd follow directions stated in the link. If you read it again, you will see why.>
As a side note, a CA reactor is the plan eventually.
<My opinion, unless you have a large system, you are better off using the Kalkwasser method
described in your link, or with manual dosing of Reef Calcium or the Tropic Marin product I mentioned earlier.
Most decent CA reactors cost 300.00 and up, and that doesn't include the media, CO2 equipment, controller, and feed pump.>
Thank you!
<You're welcome. James (Salty Dog)>

Purple Up/Coraline Algae Growth 8/1/10
Hey guys,
I hope everything is going well. I have a110 gallon system set up with some sps. My question is fairly simple. I dose C-balance in my tank and my Ca level is about 480 and the Alkalinity is 11. Mg. about 1180. I wanted to know if I can also use Purple Up in addition to the C-balance for more coraline algae growth.
<Your Ca level is a little high right now and adding Purple Up will just increase the Ca level as it does contain an ionic form of calcium which immediately raises Ca levels.>
<You're welcome. James (Salty Dog)>

Tropic Marin Bio Calcium 6/25/09
Hi there, New to WWW
<Hello Kris, welcome to our site.>
I'm inquiring on the process of adding Tropic Marin Bio-Calcium powder to my system.
First off I just got done cycling my 98 gallon FOWLR system, but have no fish added as of yet. When adding the 125 lbs. of live rock, my maint. man told me to get Tropic Marin Bio Calcium, Kent iodine, and Kent strontium.
to calcify the live rock and also get the coralline algae growth started.
While I have many folks tell me that if I don't have corals I don't need to add these things......I'm not here to debate that at this time, I'm here to ask about how to correctly add this powder to my tank now, and how to when I add fish. My guy said simply add it to the sump as directed. after 3 days of seeing un-dissolved powder on my sump floor, started thinking this wasn't an effective way.
<Not quite correct. The Tropic Marin Bio Calcium dissolves quite fast, within a minute or two. I'm going to say that you will be using approximately 4 level measuring spoons, three times per week (spoon included in can) to maintain 400ppm of calcium.>
Since there was no livestock in the aquarium, I started adding it directly to the aquarium near the incoming water to evenly spread the powder. Well I noticed a lot would simply fall down to the stand and not dissolve.
<Is best to add it to the sump where more water turbulence exists.>
When doing top offs I would add the powder to a gallon pitcher and add the mixture to the sump, I preferred this method, but now have read where this could be considered calcium carbonate and does not have many benefits.
<Calcium carbonate is the main component of shells of marine organisms and is indirectly a by product of calcium. The mixture isn't going to turn into calcium carbonate. I prefer to add the powder directly into the sump.
Mixing the powder with water creates cloudy conditions in the tank.>
I would prefer to add it daily that way, but is it loosing its purpose,
would it be harmful to fish when they are added in the next few weeks?
<Can burn both fish and invertebrates if contact is made with the powder.
This product will produce carbon dioxide when mixed. If you place some powder in a plastic glass and add water, the bottom of the glass will become very warm.
Carbon dioxide is essential to the zooxanthellae that live within the corals, it is used during photosynthesis and derived from certain calcium compounds thus making the calcium available to the coral itself. Whether you choose to use in powder form or mixed with fresh water, do add directly to the sump. Keep in mind that Tropic Marin's recommendation is to sprinkle the powder to the sump and not mix with freshwater. James (Salty Dog)>

Re: Tropic Marin Bio Calcium 6/25/09
The instructions say to put one spoon per 10 gallons a day. You think it be better 4 spoons 3 times per week? if so sounds reasonable. THANKS!
<The amount of the dose will largely depend on how many calcium loving animals you have in your tank. This is something that you will have to determine by frequent testing of calcium levels. I said "I'm guessing", and was based on my own dosage of three level spoons, three times per week in a 90 gallon long (60"x18"). My tank is moderately stocked with calcium loving animals. Do ensure that you keep your magnesium level in the range of 1250-1300 as it has much to do with calcium availability. Then get your calcium level up to 400ppm first, then start with the recommended dose and monitor daily making
adjustments if necessary. James (Salty Dog)>

Calcium additive - 02/08/09 Hello, <Hi, Minh at your service.> Just a quick question...does anybody have any experience or heard about this Part A / B , calcium/alk additives made by WM Research called CALXMAX? the price is more than B Ionic so I'm thinking this stuff must be good! Pls advise before I spent my money on something that's not worth buying . <There are some good reviews of Warner Marine's Calxmax 2 part calcium/alkalinity supplementation scheme. There are just as many if not many more positive reviews of ESV's B-Ionic system. Like these two systems, there are many others that claim to add other major, minor and trace elements along with calcium and alkalinity. The price difference between various products can be high while their promise for additional benefits may be marginal at best or fall short altogether. Keep this in mind when making your decision on which supplementation scheme to go with.> Last question (I know), is anyone from the "crew" uses this 2 part additives or everyone else is using Calcium Reactor or better yet Kalk? I'm sure Bob and Anthony are using Calcium Reactor. <We all have our own methods of maintaining calcium and alkalinity in our systems as they all have associated pros and cons. Some use commercial two part systems like ESV's B-Ionic, some use DIY two-part systems (http://www.reefkeeping.com/issues/2006-02/rhf/index.php), others like myself use Kalkwasser while there are some that use calcium reactors. The method that we decided to use is the one that best fits the needs for our system and personal schedule/budget. For example, a small soft coral bio-tope with a relatively low calcium demand would be a good candidate for a commercial two-part supplement system. If the aquarist of the same bio-tope is unable to perform daily dosing due to his/her schedule, that aquarist may elect to use Kalkwasser in an auto-top off scheme. If an aquarist needs to maintain calcium and alkalinity in a large SPS system with a high calcium demand, two-part systems become either costly or too inefficient then a calcium reactor should be employed.> Thanks in advance. Nemo1 <You're welcome. Cheers, Minh Huynh.>

Calcium Chloride Or Calcium Hydroxide 1/13/09 Team, <Aaron> I've had my 75 gallon Oceanic up and running for 2.5 years now and I've been keeping SPS corals for the past year now. Before adding SPS, I never even monitored my calcium or alkalinity or added supplements. Since starting with the SPS I've been testing my calcium/alkalinity regularly and supplementing as needed. I've been keeping the alkalinity up with Seachem Reef Builder, and I've been keeping the calcium up with Calcium Chloride I've been getting from the local science supply store. <I'm not a big fan of Calcium Chloride. It is a fast method of getting your calcium level up without the danger of raising the pH, but has no other benefits such as pH and dKH/alkalinity support. Using it long term requires constant monitoring and supplementation and frequent water changes to dilute the potentially dangerous chloride ions which can screw up your water chemistry and play havoc with calcium/alkalinity balance.> I was using about 4 tsp of Reef Builder per week and 3 tsp of dry calcium chloride per week - successfully keeping my alkalinity from 8-12 dKH and my calcium between 375 and 425 and seeing a decent amount of growth (slower than desired though) on Acros, Montis, Porites, & hydnos. I recently learned about the danger of using calcium chloride and the eventual build up of ions that will cause eminent doom for my corals and other aquarium life. <Ah, you did learn this. Great.> As a result, 3 days ago I started to drip Kalk. I've started out putting 1 tsp of pickling lime in 1 gallon of water and dripping 24/7. <As for using pickling lime, I've asked Anthony Calfo this question last year and you can read his response to me a short way down on this link. http://www.wetwebmedia.com/alkprods.htm> I have a reverse photo period in my sump with frags and macro algae, so a night only drip doesn't make sense. Am I on the right track? Do I need to do a 100% water change? Will I still need to use the Reef Builder now that I'm dripping Kalk? <Only testing will determine this.> Everything seems to be fine visually. I feel like I knew what I was doing and now I feel like I'm starting from scratch. I have succumb to the fear instilled in me by the shop keeper at the LFS. Any advice would be much appreciated. <You never mentioned using magnesium supplements. For all the calcium to be available to the corals, magnesium needs to be maintained in the area of  1280ppm. They go hand and hand. An example would be if your measured magnesium level read 650ppm, which is half of the desired level, only one half of the calcium measured in your tank would be available to the corals. So, if you are reading a calcium level of 400ppm, the corals are seeing 200ppm. I've been down that road before and I saw the benefits when calcium and magnesium are in balance. Do read here for a better understanding of calcium/alkalinity balance. http://www.wetwebmedia.com/calcalkmar.htm> Thanks! <You're welcome. James (Salty Dog)> Aaron Chandler

Calcium supplement question... culture, keeping Nephtheids   6/12/08 Hello <Howsit?> I have a 500 gallon total system for non photosynthetic organisms and have been working with Dendronephthya and Scleronephthya for some years. (I published an article on Reef Central under Dendronephthya Husbandry a few months ago about my friend Chuck Stottlemire's tank). The trouble is, Chuck's tank has done VERY well with these organisms; mine hasn't. (The trick seems to have been continuous feeding of phytoplankton and rotifer product). <Necessary... in particular, a mix of "right sized" organisms> My organisms slowly die like everyone else's. For years I have supplemented to NSW values with silica. I haven't checked the alkalinity or calcium for years, since there was little calcification/ coralline growth. <Mmm... these materials still get "used up" in captive settings> I fussed with phosphate issues, which I suspected was the problem (up to 2ppm); when I lowered the phosphate with vodka I would get initially better expansion then things worsened... <Ethanol is not a long term solution...> Long story short, I checked alkalinity and found it to be 26 DKH, calcium 280. Hmmm... no alkalinity additives for years, weekly 10% water changes with moderately hard water. After staying up half through the night trying to figure this out, I think I found the problem- chronic silica additions add alkalinity, just as nitrate additions would. (I have supplemented nitrate as well when the macroalgae shriveled with undetectable nitrate). This presumably forced the calcium down. <A mis-balance all the way around> After one large jar of calcium chloride, <... not a good idea> I got impatient and bought a calcium supplement from the pool industry; <Ditto!> I read the chemical spec sheet, and it contained 98% calcium chloride, 1% strontium chloride, and a little magnesium, no other additives. I've been spooning this stuff in. Over one week, the calcium rose to 380, the alkalinity then started to fall now in the range of 16 DKH. <You tell me what I know> I have read somewhere that some of the soft corals prefer a NSW DKH of 8-12 for optimum polyp extension, which is where I want to go. <Okay...> Needless to say, Nephtheids look terrible. However, sponges, snails, fish all look fine. Question: 1) Do you agree the silica was the cause? (Actually, my stupidity is the proximate cause, but is the silica the mediating factor?) <Only one of a few listed and not> 2) Is the pool industry additive safe? <Not really> 3) Am I going to have to ultimately add so much chloride that the whole system is poisonous and massive water changes are needed? <This would happen in time, but likely other factors will cause you to give up first> 4) If water changes, I was thinking of continuous water changes of 1000 gallons over a week or so via doser/exchanger. This would still leave about 30% or the original water in the system. Is this enough? <Likely so... I would be reading... perhaps a few good tomes on general marine aquarium water chemistry. I would (categorically) NOT use calcium chloride as a long-term, habitual supplement, NOT use C2H5OH either, NOT supplement Si02... for a system of this size, type I WOULD look into a calcium reactor, and a very large refugium and DSB and the culture (likely separately of nano, pico-plankton et al. sizes) if your intention is to sustain Nephtheids. Bob Fenner> Thanks as always Charles Matthews M.D.

Question about Ionic 2-Part Additive 5/12/08 My tank has been set up and running for about five months now and I have a fair number of calcium consuming inverts, so I monitor calcium and alk. pretty closely. <Good practice.> While I find the calcium gets depleted regularly and with consistency, my alk. seems to remain around 10 - 11 DKH and drop very, very slowly. When it gets down to 8 or so, I add some of the Alk. part of the IONIC additive and it goes up to 11-12 and begins its very slow drop. <This is a sharp increase at once. You may find they deplete at a more related rate if added at a rate with directed ratios.> Now I don't want to look a gift seahorse in the mouth here, but I am wondering what's going on. Only two possibilities come to my mind: 1) the aragonite DSB I'm using, or 2) the salt mix (tropic marin) is replenishing all that is needed. <Possibilities. What is your actual PH running?> Any thoughts on this? I'm running out of storage room for the Part 1 of the B-Ionic!! <This may just be the way your system runs, but I do suspect other factors at play. A alk swing from 8 to 12 is not small, you may need to add this more consistently than you think. The other possibility is the salt. If the salt is providing high alk and low Ca you may be compensating for this with your supplementation, giving the appearance of the Ca being depleted much faster. Scott V.>

Re: Question about Ionic 2-Part Additive 5/13/08 PH is pretty much pegged at 8.3. <Good.> I'm not sure I understand what you mean by 'adding at directed ratio's'. All I've seen says add them both equally. <The directed ratio!> I'm very concerned that if I try to add the two parts equally my ALK is going to skyrocket. <From what you are describing it is quite possible. My point was more towards adding it more often in smaller doses to avoid the 3-4 degKH swings.> Is it possible that in adding them equally, one will offset the other and allow the Alk to remain at an appropriate level? <No.> Even if this is true, why add both parts if it seems clear it only needs one? <You don't want to if you only need to add calcium.> Thanks for your help on this. <Do test your makeup and top off water for their respective KH. You are likely making up the difference somewhere. Welcome, Scott V.>

Re: Question about Ionic 2-Part Additive 5/15/08 My top off water is aerated RO/DI with no buffer. I can only think that it's the Tropic Marin doing it. <Must be, high in alk.> I change water once a week and it seems to be enough to handle my Alk. needs. Presumably as time goes on, the acidity in the tank will increase and the need for buffer will increase as well. Thanks for the help. <Welcome, happy reefing, Scott V.>

Re: percula clownfish eggs about to hatch... and DIY suppler of 2 part SW supplement for Ca and Alk   4/29/08 Hi, and thanks for the help on my serendipitous clownfish spawn (hoping the hatch is not before Friday). You asked about my "home-made" two-part additive. Actually it is just the basic kit from www.bulkreefsupply.com. For about $50 I have a lifetime supply of calcium supplement plus alkalinity plus magnesium occasionally. Highly recommended. Thanks again, Malcolm Young <Thank you for sending this along. BobF> Liquid Calcium and Alkalinity -- 04/02/08 Hello, <<Hi there>> Well, I can now personally attest to the drawbacks of liquid calcium? <<Oh?>> After maintaining a dKH of 10 for months, I now can't get it over 7 dKH after using liquid calcium (calcium chloride) for months. <<Ah, I see'¦the buildup of Chloride ions have thrown your water chemistry 'out of balance''¦as you seem to be aware>> It appears the chloride ions have run amuck. <<Indeed>> Any idea how to get the dKH back up to 10 or so? <<Mmm, yes'¦several large water changes should make a difference as you need to remove/dilute the Chloride ions in the system>> I've added Seachem alkalinity buffer, but it's not helping much before the pH gets too high (8.5). <<And the 'opposite' is usually the case with this product'¦evidence of the high Chloride residual possibly>> Is a dKH of 7 bad in a reef aquarium? <<It's not 'bad''¦but 8 dKH or higher is preferred>> All inhabitants are fine, but coralline growth has slowed. <<No need for panic at this point... Do the water changes and conditions should improve/balance should return. Then, research some alternate methods for Calcium supplementation. Calcium Chloride is fine for the 'occasional adjustment,' but really should be avoided for 'continuous and frequent' use>> Thanks, Greg <<Happy to share. EricR>>

Liquid Calcium...Safe To 'Boost' New Saltwater? -- 07/23/07 Hey guys. <<Howdy Steve>> I have been reading your articles for several years now, you guys are great. <<Thank you...quite the collective effort, indeed>> Here is my situation: I have noticed that the IO Reef Crystals salt that I am using only mixes to 340ppm of calcium. <<Mmm, just a 'personal' comment...I have been very unhappy with Instant Ocean these past months...am suspecting a formula change or a possible loss of quality control...will be making the switch to Seachem very soon>> I am using C-Balance in my 55-gallon reef to maintain proper calcium and alkalinity. Can I use Kent Marine liquid calcium in my freshly mixed saltwater? <<You can, yes>> I have read about all of the drawbacks in using liquid calcium so I have tried to stay away. <<Mmm, yes...possible buildup of Chloride...though maybe not that much of an issue after all>> However, I figured that the 5-gallons per week that I am replacing really is not that much'¦so there won't really be any ill effects. I have found that 5ml of the liquid calcium will get to me to around 400pm of calcium in my 5 gallon bucket. Can you think of any drawback that this would have for my tank in the long term? I am thinking it will be ok'¦ Steve <<And it probably will... There 'may' be some concern over long-term buildup of Chloride ions...and if you wish to avoid such you could use a Calcium Acetate or Calcium Gluconate product, or even simple Kalkwasser. EricR>>

Fiji Gold   3/29/07 Quick question please.............   How do you guys feel about "Fiji Gold" as a calcium supplement? <As posted on WWM:  "Mmm, a mix of sodium bicarbonate, calcium chloride, calcium carbonate and a little borate. I gave the formulation for this "Fiji Gold" (delicious, export <FYI is also the name of a beer... Bob, like Homer Simpson... beeeeer... here being temporarily distracted.>) to Walt.S sometime ago and strongly suggested he market same and place a sample in each box of live rock, faux and natural... Bob Fenner"> I am dosing it once a week as it states on the jar. <Monitor levels.  More here:   http://www.wetwebmedia.com/calcalkmar.htm > Should I supplement any other minerals or is it true what they say on the package that it includes all the minerals in their "natural" state. <Yes, is crushed coral skeletons plus.>   Please let me know what you think about this product. <Bob, inspired by said export, named it.>      Thanks, <Welcome, -Mich> Jeromy  PS- thanks for all the help in the past!!!!! <On behalf of the crew, you're quite welcome.>

Calcium Additives 3/28/07 Hello folks, <Hi Mike> I have a 150 gallon SPS tank with roughly 250 lbs. of LR.  My params are: Ca 315, Mg 1275, Alk 10.5 dKH, specific gravity 1.026, and PH 8.2-8.28.  The Ca had dropped form 380 down to current level over a period of time because the Mg was down to 1025, but over the past 3-4 wks, I've slowly raised the Mg up to it's current level.  I was wondering what would be the "best" device to use to bump the Ca back up into the upper 300s.  My LFS really push the Turbo Calcium, but I've read some not so glowing reviews about it's use. <Not familiar or have used the product.  I get turned off on products with prefixes such as Turbo, Supercharge, etc.> I also run a  Ca reactor.  Any suggestions would be greatly appreciated. <I'm thinking if all is well with the reactor, that alone should suffice. But, you could use Kalkwasser or a product such as SeaChem's Reef Calcium or other similar products.> Thanks again, <You're welcome.  James (Salty Dog)> Mike

pH and Calcium supplements 4/10/06 What product do you recommend to raise pH and calcium levels? <<Be sure you understand and test for Alkalinity.  pH measures how acidic or basic the water is.  Alkalinity measures the buffering capacity of the water, or in other words, the ability of the water to resist changes in pH.  Both are very important, and alkalinity is widely under-appreciated.  In any case, Kalkwasser is very useful in supporting pH, Alkalinity and calcium.  It is cheap and easy to use.  Grocery store pickling lime can be substituted for cost savings.  B-Ionic by ESV, C-Balance by Twolittlefishies and TechAB by Kent are all two part preparations (one part calcium, one part alkalinity) that work extremely well and are extremely convenient to use, but are somewhat expensive.  There are recipes for "home brew" two part additives floating about the internet, but are probably best followed only by those with some chemistry background.  Last, but not least... you can use commercially available dry calcium and alkalinity additives. They are cheaper than two part additive systems but require a bit more care in their use.  Tropic-Marin makes a great dry product called BioCalcium that adds calcium and alkalinity in one product.  Any of the above can work very well.  Best Regards.  AdamC.>>

Calcium Additives For Marine Aquarium - 03/15/2006 I have a 55 gallon tank recently setup with 25 LBS live rock, CPR dx6 protein skimmer, cs150 CPR overflow. I have 2 inches of live sand and other sand for substrate. No fish yet. I also am using RO/DI water for water changes and maintenance. I am looking into calcium and its effects. Your site is great and a little overwhelmed by information. My question is Kalkwasser, which is the best supplements to use? <Unless you fully understand the effects of Kalkwasser, you would probably be better served by another choice. The Kalkwasser would change your chemistry "ball game". Can you suggest which way to go with using Kalkwasser or just straight calcium products and which has had more success. <Too much to try and cover in e-mail. Try studying here   http://www.wetwebmedia.com/calcalkmar.htm and the related links above. Bottom line though, if you feel uncomfortable with it don't use it. A good frequent water change schedule (with properly prepared water) would be best. Eliminates the need for much of these.> Thanks Cary <You're welcome. - Josh>

WWM Question on Substrates part 3 4/16/06 How much turn over do you recommend for a tank? Is that filtered or just movement? <<For a reef tank, turn over of at least 10x the tank volume is ideal.  Some aquarists use 20x or more.  Those figures apply to the amount of water movement within the tank.  This can be provided by return pumps, powerheads, power filters, etc., but in-sump protein skimmers don't count.>> What about Aragamite or Aragamilk? <<These products are nearly useless for maintenance of calcium and alkalinity since like aragonite sand, they are practically insoluble at normal reef tank pH.  Best Regards, AdamC.> Kalkwasser Reactor versus Calcium Reactor - 05/26/06 ** High Priority ** ** Reply Requested When Convenient ** Please help. <<I shall try>> I am getting bombarded with "best practice" suggestions.  I've read that some run both units (Kalk reactor/calcium reactor) -- using the elevated pH effect of the Kalkwasser addition at night to offset the reduction in pH caused by CO2. <<This is one approach.  I have/use both reactors...but mine are in operation 24/7>> Others suggest getting either unit to supplement calcium levels. <<If I could only use one, it would be the Kalk reactor>> Others maintain that Kalkwasser is the better option with noting but benefits provided it is administered correctly (i.e. limited to night only when pH levels are usually depressed) <<I disagree on the application.  When using a Kalkwasser reactor in conjunction with an auto top-off unit there is little (if any!) danger/more benefit to letting it operate "'round the clock" in my opinion>> I have started using a Kalkwasser stirrer with a dosing pump to add all my RO top-up water to the tank at NIGHT ONLY. <<Truly no need for this hassle...hook it up and let it operate 24/7>> I have been naively adding 2 tablespoons of Kalkwasser to the unit every 2 weeks and leaving it to run on an automatic float switch. <<Mmm, is this per the instructions with the unit?  You likely need to add more than this for a two week period>> Now I have just been told that this is dangerous and can stuff up pH levels and in the long term drop alkalinity!!! <<Not when used merely for top-off/evaporation replacement...as long as you are "dosing" small amounts on a frequent basis and not waiting till you need to add a gallon of water to top up the tank>> I am totally bewildered -- please advise what is best practice when using Kalk Stirrer? <<Just as I've stated...but feel free to write back to me if you need further clarification>> And would you advise that I look at getting rid of the stirrer and replacing it with a calcium reactor instead? <<Nope...use both if you have them>> Or is having both units better? <<I think so, yes...but is not a necessity>> Regards Rayven Durban, South Africa <<Cheers, Eric Russell...Columbia, South Carolina>>

Dosing Ca HI Do you recommend using Reef Builder or Reef Carbonate along with the Reef Advantage? Or will the excess carbonate throw off my other parameters like pH and ALK?  <You may not have to add anything else. Just check your dKH and try to maintain between 8-12dkh. I would use Reef Builder if needed. James (Salty Dog)> 

Calcium Hello,  <Hello Saurav> Thanks for all your help you guys are great.  <You're welcome>  I wrote you guys before because I was having problems with high ALK and high Ca. I changed from Oceanic to Instant Ocean salt and with water changes the level reduced. I am interested now in getting SPS corals. I think I have to start dosing Ca, my number at 420 will reduce I think with more water changes as it has. By the way my ALK is 3.5 meq/L and pH is 8.4. Do you recommend I start dosing Ca?  <I would maintain 400ppm>  If so what do you recommend to dose with. I have a 55 gallon tank and Kalkwasser seems to be meant for larger tanks and Ca reactors are pricey. What do you think of Kent Marine Liquid Ca? If you do not think I should start dosing now at what Ca level will it be appropriate time to start dosing?  <As above>  Also will SPS corals, as far as lighting goes, will do ok in my tank particularly Acropora and Montipora? I have 265 Watts of power compact lighting. Thanks again!  <Personally I like SeaChem's Reef Advantage (dry form). It also includes magnesium and strontium, two important elements. It does not have a caustic ph like Kalkwasser and will not deplete alkalinity. As far as keeping monti's and Acroporas or flower pot corals, your lighting would be a bit on borderline, most other corals you could keep. James (Salty Dog)>

Kalk slurry excerpt (from BOCP1) redux redux 6/5/03 Anthony.... Could you describe your Kalk slurry method (mixing & administering) please?? Thank you, Pat Marren <indeed my friend. Let me direct you to our archives (really the best way to find extensive data you seek and more... the key is learning to use and manipulate the google.com search tool for our site on the main index page for WWM. In this case I cheated and typed in "Kalk slurry excerpt" and found three pages with it included: http://www.wetwebmedia.com/kalkh20faq2.htm http://www.wetwebmedia.com/circmarfaq3.htm http://www.wetwebmedia.com/corlalgfaqs2.htm if you follow the many links on and atop these pages, there is a lot of other interesting data to be found. Kind regards, Anthony>

Re: Slurry question II 6/4/03 Thank you for the quick response Anthony.   <always welcome my friend> You know I have read the marble analogy in your book and on the website, problem was I thought that 11 dKH was considered more optimum and not real high, with high being more in the teens, duh!.    <definitely a hazy range of tolerance to be sure. And I would not say your ALK is dangerous at all at 11 dKH... just sitting on the higher end of the ideal (8-12 dKH). Unfortunately, the aggressive SPS and clam keepers preach much higher levels of Ca and ALK without  lending strong admonitions to non-SPS keepers (and folks without reliable calcium reactors) of the precarious if not dangerous line that is to walk for most folks. It can be done... but only with strict supervision and usually by coral farmers needing the extra growth and willing to take the risks. For most aquarists that want good growth, but stable and reliable... 8-12 dKH is ducky, and 350-425 ppm Calcium is realistic, but both are not to be pushed high at the same time> The bummer of it all is that it was about 8 dKH or so and I added some baking soda to move it up!  Curses!  So I assume it will drop over time then.   <yes my friend... simply let it stray down over days and then resume normal supplementation> Ok, I have another question, stupid as it may be, but  here goes.  You mention that calcium gluconate is great for growing coralline algae, but not good for much else, correct.   <exactly... corals take up various forms of calcium in different preferences... under 75 F they also take Strontium to make strontium carbonate skeletons, over 75 they take Calcium carbonate in preference, etc> Does it raise the level of calcium in your tank?   <it does... just not the ideal/usable calcium> I guess what I am asking, does it matter what type of calcium is added to your tank.  Can too much of any type cause the "overflow of marbles" so to speak and cause a "snowstorm"? <correct again... although it is usually only sever if you dose large amount fast, or generally large amounts over an extended period of time> If I wanted to get my calcium up there, but my ph is at 8.3 - 8.4, could I use Calcium Chloride just once or twice to get the numbers up without using the buffer ( Ionic A and B, skip the B part ), or is this too dangerous. <nope... I do believe that would be fine for a quick fix. Exactly as it was designed for> thanks Paul <kindly, Anthony>

Re: Calcium supplement Brands When I emailed my local fish store to ask if they had these products that you recommended below they had this to say: "I hate Seachem Products. You should be using Reef Former for Calcium, Sealk for ph and alkalinity, and you also need to use mg up which is magnesium along with the calcium because calcium cannot be used by anything without magnesium." Jason Booth Aquatic Realm "The Aquarium Experts" <did they explain why they don't like Seachem products? It may be that they don't have a convenient distributor or that the product they recommend are more profitable <G>. Perhaps they simply haven't taken a good enough look at the company. Founded by a chemist... time tested and proven reputation of the company... extensive research and development of products as well as quality control... and they invest in the hobby/industry (aquarium societies, conferences/trade shows). They are a fantastic business model for a company that makes good products: period. And I say this as a consumer of their products for over ten years (and not one free sample <VBG>). > Is this true? Should I be using mg?  <it is helpful to test for magnesium although dosing is minimal if at all for most aquarists doing regular water changes. Mag levels should basically be about three times calcium levels. So... 400 ppm calcium and 1200 ppm Mg would be fine. Most aquarists that have fantastic reef tanks, do regular water changes and maintain adequate ALK and CA... never test for or dose Mg. My advice is in fact to do so anyway... an inexpensive test and its nice to have another reference point> I haven't been so what harm have I done if any?  <likely no harm at all my friend> Do you like the products he mentions or is your opinion to still go with Seachem?  <The NatuReef products he mentions might be very fine. I've never tried them and am not likely to in the near future. Seachem is simply a big company with a long standing reputation for excellence. I like to buy my products from such companies. That's why I like using Instant Ocean sea salt (and many agree). Sure there might be salts with slighter higher levels of some minerals... but Instant Ocean's consistency and quality control is unmatched. They are the biggest... and they were the pioneers in the industry. For that they get customer loyalty. > I put a lot more value on your opinion than Jason's but wanted to see what you had to say before I purchased anything. Thanks so much for your help. :) <quite welcome... thank you for inviting me to do this infomercial...heehee. Many fine products out there. Indeed, just make a consensus and pick one that you can live with. Its sometimes interesting to do a keyword search on some of the big message boards for these brand names and see which ones get consistent high marks and which ones have their share of flak. Kindly, Anthony>

Calcium  Just wanted to get your thoughts, pros cons, on using SeaChem's liquid "reef complete" and "reef calcium" to increase and maintain calcium levels.  <I would not use liquid calcium chloride (reef complete) to raise and maintain calcium from ANY brand! There are serious complications down the road from doing this (accumulated Chloride ions skewing Ca/ALK dynamic causing precip). Calcium Chloride is a temporary calcium fix when needed fast without a pH rise. Kalkwasser has so many more benefits anyway. Reef Calcium on the other hand is a sugar based calcium (gluconate) and although still useless for Ca levels and coral growth... it is OUTSTANDING for coralline algae growth. I highly recommend the use of SeaChem's Reef Calcium with Kalkwasser or a calcium reactor for good coralline algae and coral growth> I read and hear that the best way to do it is by using Kalkwasser for different reasons,  <absolutely correct! Many advantages including phosphate precip, saponification (improving skimmate production), protecting ALK, etc)> but I'm trying to avoid setting up a limewater drip system. <HA... too bad... deal with it kid :) Actually... a Ca reactor would be too expensive here understood. Do consider my Kalk slurry method. Detailed in my book of coral propagation and discussed at length on Reefcentral's message board (do a simple keyword search) or look into our archives on Calcium. Many other great things to learn about calcium in the WetWebMedia archives and FAQs> I have a fairly small tank, 46 gallon. Thanks, Angelo<best regards, Anthony Calfo>

Calcium  Just wanted to get your thoughts, pros cons, on using SeaChem's liquid "reef complete" and "reef calcium" to increase and maintain calcium levels.  <I would not use liquid calcium chloride (reef complete) to raise and maintain calcium from ANY brand! There are serious complications down the road from doing this (accumulated Chloride ions skewing Ca/ALK dynamic causing precip). Calcium Chloride is a temporary calcium fix when needed fast without a pH rise. Kalkwasser has so many more benefits anyway. Reef Calcium on the other hand is a sugar based calcium (gluconate) and although still useless for Ca levels and coral growth... it is OUTSTANDING for coralline algae growth. I highly recommend the use of SeaChem's Reef Calcium with Kalkwasser or a calcium reactor for good coralline algae and coral growth> I read and hear that the best way to do it is by using Kalkwasser for different reasons,  <absolutely correct! Many advantages including phosphate precip, saponification (improving skimmate production), protecting ALK, etc)> but I'm trying to avoid setting up a limewater drip system. <HA... too bad... deal with it kid :) Actually... a Ca reactor would be too expensive here understood. Do consider my Kalk slurry method. Detailed in my book of coral propagation and discussed at length on Reefcentral's message board (do a simple keyword search) or look into our archives on Calcium. Many other great things to learn about calcium in the WetWebMedia archives and FAQs> I have a fairly small tank, 46 gallon. Thanks, Angelo<best regards, Anthony Calfo>

Calcium supplement What brand of calcium supplement would you recommend for live rock? <for coralline growth only I really like Seachem's Reef Calcium (an organic sugar-based calcium gluconate). Simply outstanding for growing coralline algae (pink/purple, etc). 4 months of faithful use and it will look like a whole new tank :) For coral growth however, Kalkwasser supported by proper alkalinity (buffer) is recommended when a calcium reactor is not possible/present. I use a Knop calcium reactor from General Aquatics for convenience but still like Kalkwasser very much. Best regards, Anthony> Elizabeth K. Birdwell

Another question about Calcium Bob, Thanks for all of your help over the years, I hope you know you are appreciated! Anyhow, I am at a crossroads with making a decision on Calcium Supplementation. I am sure you have heard this before but the issues as I see them are: 1) I could set up a top off system,( which I will be doing in any case) and buy/make and Nilsen reactor. Obviously, PH is an issue and as a natural combatant of Phosphates, this may be a nice option. <and one that I favor strongly> 2) Do a freshwater top off but supplement Calcium with a Calcium Reactor. This option obviously has some nice features in that trace elements, Alkalinity and Calcium levels will be maintained. This seems to be a more automated solution. <yes... but even Daniel Knop of Knop reactors like most experienced aquarists recognize and/or advocate Kalkwasser supplementation to reactors which are predominantly Alkalinity generators> The real question becomes, can an automated Kalkwasser delivery system provide everything that the reactor will?  <they are separate... Kalk/Lime provides calcium only and protects the buffering pool of alkalinity by virtue of its caustic nature (high pH). Reactors are predominantly for raising alkalinity although they certainly do contribute measurably to calcium levels. Aquaria with the fastest growth, if this is your goal, employ both. Do review our Archives and article by Jason C on this subject> I am assuming I will need to supplement a Alkalinity buffer with Limewater only.  <agreed> I know you can do both and maybe that is the best of both worlds.  <very wise my friend!> I would love to hear your opinion on the issues. Thanks! Adam <you know all that you need to continue on this wonderful journey! Kindly, Anthony Calfo>

Calcium Bob, <Actually, Steven Pro right now.> I did some studying and I have been able to maintain 3.0 meq/l of Alk and a pH of 8.2. Over a five day period I have been able to maintain the above parameters. I tested everyday and my SG is 1.023. My calcium has depleted form 350 ppm to 300, there is not a heavy amount of fish or invertebrates. I would like to raise the calcium without lowering my Alk. Would a Kalkwasser drip be good enough to maintain a 350-400 ppm of calcium? Thanks <Kalkwasser is my current preferred method. -Steven Pro>

Calcium supplements Hey fellas! What's up? Just a quick question, what's y'alls opinion of Bio calcium by Tropic Marin? <A very good product> Is it better/as good as Kalkwasser mixes? <Mmm, better IMO> It sure is a lot easier to use! I have been using it for a while now and it seems to be working good, just wanted to know what y'all think. Also, I would like to know if you think I could keep SPS corals healthy in my system, I have a 70 gallon tank with 440 watts of VHO lighting, 70 lbs of 9year old live rock and an old CC skimmer powered with a Tetra Luft pump. <I might renew/replace some of the old live rock... otherwise you're ready> I have been keeping corals for almost 10 years but have never tried SPS before. I have had several people tell me that you must have MH lighting for these animals, yet other people such as GARF) do not seem to have this opinion!? <Neither do I. Am familiar with folks who make a living culturing corals using PCs> What do y'all think? Also, one last thing, for the last 4 years I have been using a home made wave maker Radio Shack-$25.00) with good results set at 15 second intervals running 4 pumps,2 high, 2 low in rockwork, but have lately been reading about how bad laminar flow is for tanks, any suggestions on reconfiguring what I currently have or should I buy some sweeping powerheads, and if I do, should they be on a timer/wavemaker as well or just plugged in?  <Mmm, should be fine either way... as long as the water flow/force isn't overpowering whatever life you have it directed at> Y'all have a great site and do a great service of separating Bunk from Knowledge! Thanking you in advance, Joshua Scialdone P.S. Guess this was more than one simple Question! Ha Ha Ha Thanks Again, Joshua <Be chatting Josh. Bob Fenner>

Calcium Additions What's up guys? I have a 75gal fish only setup and just recently added my first live rock (only 20lbs.). Should I be adding a calcium buffer? <Before adding any supplement for calcium, you need to have a test kit. You must monitor your calcium levels and trends in relation to your dosing.> What level should I keep calcium at? <350-500 ppm depending on alkalinity level.> Do I continue to use my PH buffer (8.3) with water changes? <Same as above with calcium. Your test kit will tell you whether you need to or not.> Thanks, Mark <You are welcome. -Steven Pro>

Ca Chloride and 2-part Additive Question Hello there, I have read that Ca Chloride is "bad" for my tank, in the long run. <Yes> I use a two-part additive called Oceans Blend, which lists chloride as one of its ingredients, but it's mixed with a ton of other elements (essential elements, carbonate, etc) and appears to be "balanced." <Correct> When the literature/FAQ's state that chloride is bad, are they referring to things like Turbo Ca, which is just Ca Chloride (i.e., additives that are Ca Chloride only) <Yes> or do they mean anything with chloride in it? <No, actually your salt mix has chloride in it. It is all about balance. These two part formulations are designed to add calcium and carbonate along with many other things.> If so, do other 2-parts like B-Ionic contain chloride? <Yes> I have read good things about this product and may switch if this is a safer additive. BTW, I'm gonna throw this question out to the chat forum section on the site to get more input. I hope this is not considered rude/bad etiquette. <No, we always recommend other seek more advise and knowledge so they can make their own informed decision.> Thanks a bunch, -RY <You are welcome. P.S. Your question shows you are reading and thinking a lot. Kudos to you. -Steven Pro>

Is there a big difference in the effectiveness of using a calcium reactor compared to using, lets say, "C-Balance" liquid calcium additives? >> Yes, huge differences... the calcium reactor works to adjust pH, alkalinity and biomineral (depending on the feeder stock you use... just calcium to strontium, magnesium and more in addition) continuously... The two part additives, liquid calcium additives... can only hope to approximate these balanced needs... In particular is the paradox of increasing calcium at the expense of decreasing alkalinity... with the additive game... A few years from now, all serious marine aquarists will have calcium reactors. Bob Fenner

Calcium low Hi my name is John, I know Mike Kaechele from Scripps hospital who says he is a friend of yours (Sorry if I did not spell his last name right). I have a question about my 55gal reef tank. It has low calcium levels (270-300ppm). It has about 45-50 pounds of live rock in it with three hard corals in it (frog spawn, torch, and a plate coral). I checked the magnesium levels and it was a little low so I raised it up a little (1100 ppm to 1300ppm) and I am drip feeding Kalkwasser into the tank nightly and sometimes daily. I just brought the magnesium up about a week ago so I am thinking to give more time or there just maybe to many organisms sucking it down as fast as I put it in. Can you please let me know what you think. Thanks John  >> Nice to meet you. About how did/are you elevating the magnesium concentration? If by means of Epsom salt (MgSO4), you should keep adding this... slowly. The Kalkwasser additions by night should show more increase with time... but I'm concerned about the ancillary effects of low alkalinity... Do us the favor of reading through the articles and FAQ files on our site: Home Page to gain an understanding of the antagonistic effects of these phenomena... and we'll chat. Bob Fenner

Re: calcium low Thanks for responding back. Yes I used Epsom salt and yes I did it very slowly. As for the alk levels they are about 8-10 dKH... Thanks John >> Ah, well am I answered. All sounds fine. Bob Fenner

Alkalinity/Calcium relationship Hey Bob, I hope everything is well with you. I have read your responses and information regarding alkalinity and calcium level issues, but I still have a question regarding my system - my calcium levels are testing in the 480 to 500 ppm range, but my alkalinity is still in the 2.5 to 2.75 meq/l range. How should I raise the alkalinity level without further increasing the calcium level? <A few things could be done...> I have recently purchased the two part Kent Marine A & B products, but I am now afraid to use this since my calcium levels are high. Baking soda?  <The "B" is ostensibly this...> If so, how much? <Try a teaspoon per ten gallons... mixed in with system water... drip about half in and re-measure/test...> What about the SeaChem marine buffer 8.3 ph product? <A good mix of carbonates, bicarbonates...> I have a 92 gallon reef set up with 5 small fish, cleaner shrimp, various clean-up crew members, and 5 hardy type corals. My tank is about 8 months old and has maintained good consistent water parameters otherwise. Thank you! <You're likely aware of my liking of calcium reactors (calcium carbonate et al. stocks melted down by carbonic acid/carbon dioxide in solution... this is the single best method of achieving the ends you seek (stable, optimized pH, biomineral content and alkalinity)... For alkalinity alone, you want to add, slowly a mix of carbonates, bicarbonates (not just the latter through baking soda in the long haul)... can be added through compounds that contain both (as in one/two part products made in/for the trade/hobby... or you can buy/administer the same materials... A few co-factors do help... skimming, water changing, a dearth of feeding, adequate light/photosynthesis, ozone use/UV use... aeration/circulation... Bob Fenner>

Calcium level what is the correct calcium level for salt water.  <Depends on a few factors...types of livestock, what you're trying to do with them... but somewhere between 350-400ppm> also, i bought a bottle of calcium chloride, is this ok to use. <Can be... to initially boost free calcium... not safe to use to move all at once, continuously...> also, is Kalkwasser the best additive for calcium, or is liquid calcium, like what i bought ok. thank you <Best? None at all... somewhere between... calcium reactors of a few designs... You need to study my friend... not ask questions here... Do get/read over some of the current text works in the field of marine aquarium keeping, join a listserv on the net... read over the WWM site... these basic questions are all answered more completely on the stated forums. Bob Fenner>

Calcium (additives, alternatives) Hi Bob, Here's another version of the bazillion dollar question for you. Tank: 90gal, 90lbs LR, 80lbs cc, 30gal sump w/ DSB and Caulerpa, amm, nitrite 0, nitrate 10ppm, 80F, 1.023, (tank is fallow, will raise temp and lower salinity soon), ph 8.4, alk 3.4 meq/l, ca 250-300. Tank inhabitants include 2 cleaner shrimp, 1 peppermint shrimp, snails and hermits, 1 leather toadstool, some polyps and mushrooms. I'm trying to boost coralline growth. I'm adding C-balance to try to raise my calcium levels, which have never gone higher than 300. I've tried a large water change to try to "re-center" my system. Would it be a good idea to add calcium chloride in addition to the 2-part ca/buffer solutions?  <Yes... worth trying... a bit at a time... like a half gram or so> Or use the calcium chloride alone until I get desired ca levels, then use the C-balance?  <Better to use a little of both> Isn't it basically the same as the "part A" of the C-balance?  <To a good extent yes... I might also experiment with the addition of an ounce or so of baking soda (sodium bicarbonate) per day> I have access to calcium chloride dehydrate. How much of this should I add to say, 1 gal of water before dripping into my system? Sorry, for the book. I know you recommend ca reactors, but I need a temporary solution I can use while I save up the $400 bucks or so needed for the reactor. Thanks. <As Captain Jean Luc might say, "Make it so". Bob Fenner>

Re: Calcium Hi Bob, Thanks for the quick reply. Forgot to mention, but yes, I will also add baking soda along with the calcium chloride to keep up my alk levels. I will also be testing for ph, ca and alk throughout the whole process. <Ah, certainly> Another question, if calcium chloride combined with baking soda is basically the same as the 2 part ca/buffer additives, what's the benefit to using the more expensive 2 part additives? <Hmm, there are some other compounds... a bit of borate, calcium carbonate... finely ground, proportionalized, neatly bottled and labeled... As with other chemical products, a matter of convenience, cost> Wouldn't regular water changes replenish all the remaining minerals provided by the additives? <Yowzah! This is a bold statement... and true, given "enough water change"... as in "lots"... We can carry on this discussion if you'd like> I'm just trying to get a clearer understanding of what I'm putting into my system. Thanks for helping me get "there". <You are expanding your consciousness in important ways here my friend. Don't allow your mind in terms of feelings to become fixated. Bob Fenner>

Calcium conundrum 8.10.05 Hello, crew.  I love the site.  I've gotten SOOO much good stuff from you guys! Anyways, I'm writing to see if you guys can shed some light on what appears to be conflicting information on calcium supplementation.  To start off, we have three tanks -- 46 gal reef, 11 gal nanoreef for a mantis, and just revving up a 120 gal FOWLR.  The two reef tanks are happy and healthy with respect to Ca/Alk (Ca around 350, Alk around 3.5 meq/L, pH 8.1-8.3), <Good readings... but no lower on the pH please for invert tanks. Many corals are irritated by flat pH> and the FO is getting there (just finishing cycling). My concern is over the product(s) you guys recommend for maintaining calcium/alk.  The LFS (Aquatics Warehouse in San Diego -- NICE place) suggests Reef Builder/Reef Complete along with SeaChem buffer as needed.  We used this successfully for about a year, but then I read that you guys really frown upon the use of calcium chloride (the primary ingredient of Reef Complete).   <Correct... when used as a principal means of calcium supplementation in tanks that do not get very large, regular water changes. Moreover, other Ca supplements like common Calcium hydroxide have other benefits that are well documented> So, we switched to Reef Calcium (calcium gluconate)... but then I read from you that it doesn't do squat for coral growth (although it says so on the bottle?).   <An exaggeration... but yes, you will find I think that a tank using polygluconate with not grow corals as fast as with calcium hydroxide or a calcium reactor. The Gluconate is very good for coralline algae growth, however> I'd rather not handle Calcium Hydroxide directly if I can help it. <Really... its no more dangerous than any of a number of other reef or household chemicals> Looking at SeaChem's other products, I see "Reef Advantage Calcium", but that seems to be just Reef Complete (although I've seen this product recommended in the FAQs by some of the crew members).  Various "two-part" systems say that they contain "balanced ionic calcium" but don't give more details. <The two-part supplements are very fine assuming you start with a tank that is already in balance (or do a very large water change to return the tank to balance> Can you help clear this up?  If you were to pick a liquid or powdered Ca supplement for systems with relatively light calcium intake loads (soft corals, a few LPS), what would it be? <I'd choose a good two-part supplement if I had to use liquid> Thanks! Dan <Best regards, Anthony>

Become a Sponsor Features:
Daily FAQs FW Daily FAQs SW Pix of the Day FW Pix of the Day New On WWM
Helpful Links Hobbyist Forum Calendars Admin Index Cover Images
Featured Sponsors: