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FAQs on Calcium Reactors, Selection

Related Articles: Calcium Reactors and How They Work by James Gasta, Calcium Reactors: The Top 10 (Plus) Frequently Asked Questions about Calcium Reactors by Jason Chodakowski, Calcium, Understanding Calcium & Alkalinity, Kalkwasser, Calcium Reactors

Related FAQs: Calcium Reactors 1Calcium Reactors 2Calcium Reactors 3Calcium Reactors 4, Calcium Reactors 5, & FAQs on Calcium Reactors: Rationale/Use, Installation, Operation, Media, Measuring, Trouble-Shooting, By Makes/Models, & Calcium and Alkalinity,  & FAQs on: The Science of Calcium & Alkalinity, Importance, Measure, Sources, Use of AdditivesTroubleshooting/Fixing, Products,

There is a wide range of "utility" in different makes, models and DIY Ca reactor designs... Look to your actual current and future needs, as well as the very real cost of your time in fooling with such gear... Ask around... the specialty BB's re actual users experiences is my advice. RMF.

Calcium Reactor (Selection) -- 08/16/09
<<Hi Nathan>>
I am planning on adding a calcium reactor to my 120 and 60 gallon tanks that share a 30 gallon sump and a 30 gallon remote deep sand bed.
I've owned the Knop HD previously for a brief period of time and it seemed to do well. This time I think I've narrowed it down between the Korallin C 3002 and the Knop S-IV. I thought I'd ask which one you guys would most highly suggest among the two or perhaps a 3rd party I haven't considered.
<<There are several good choices available (Knop, Precision Marine, Deltec, AquaC, Korallin, etc.). The things to look for are capacity (is it 'big enough' to do the job), ease of access for media replacement (Knop's earlier models have always excelled here'¦and AquaC looks to be following their lead), quality of the circulation pump (I 'really' like Eheim pumps for this), and of course the quality of the materials and workmanship (acrylic vs. plastic/polypropylene, PVC pipe vs. molded plastic pipe, 'welded' joints, etc.). Either choice you have listed would be fine'¦but if you're willing to spend the money on the Knop unit, 'I' would go the extra $16.00 and get the Knop HD (assuming you have space for it) for its design and means of media access>>
Also, I'd like to have it with a pH controller; would you recommend the American Marine, Milwaukee, or Aquamedic pH computer?
<<All will serve (but I am partial to American Marine's product line), though in my opinion a 'controller' for a calcium reactor is not a necessity>>
Thanks in advance,
<<Happy to share my friend'¦ EricR>>
Re: Calcium Reactor (Selection) -- 08/17/09

So you think the HD is actually better than the S-IV then,
<<I like the design of the Knop HD better, yes>>
ok, I'll probably go with another one of those. What do you suggest for media reference phosphate content, Korallith or ARM?
<<I've read test results where the ARM media displayed a lower Phosphate content than the Korallith media. But, Phosphate content isn't the whole story when it comes to reactor media'¦and I also can't be sure of the accuracy of these tests. I have used both and can't say I've noticed any appreciable differences between the two in how my tank reacts, and any 'Phosphate Issues' with one's tank likely stem from other sources anyway (e.g. -- foods). The decision is yours of course'¦you can peruse the forums and go with the popular choice'¦but my suggestion with reactor media is; like with salt mixes, buy a couple to three different brands and mix/use them in conjunction>>
Thanks again,
<<Always welcome'¦ EricR>>
R2: Calcium Reactor (Selection) -- 08/21/09

Roger that, I just ordered a Knop HD with some Korallith and ARM, both in the coarse variety. Would you have picked up a different size media?
<<Nope, I too prefer a coarse medium'¦less tendency to 'pack'>>
Also, I am starting out with a 5 lb CO2 tank; when I had my Knop HD the last time I had a 15 pounder neither of which I was able to keep for more than a few months...
<<Dang'¦must have had that puppy cranked! I'm not saying you were doing anything wrong. Every system is unique, and your reactor needs to be set up/tuned re'¦but my 10lb bottle yields about a year or more of use between fills>>
How long do you suppose 5lbs of CO2 will last?
<<Mmm'¦about a third as long as the 15-pounder, at that same bubble rate [grin]. Do be sure to peruse our data on reactor use/settings'¦and bio-mineral use/their relationships. Here's some links to help get you started:
Thanks again Eric!
<<Always happy to share Nathan. EricR>>

Calcium Reactor Upgrade, sel.      12/15/08 Hello Media Crew, <Matthew> I have been fidgeting and fussing around with my Knop C for sometime now. Its for a 200 gal sps system. <Mmm, okay> Everyday it requires readjusting of the effluent dropper, keeps getting clogged/loses consistency intraday...very time consuming and unstable for corals & constantly having to test for KH & calcium. I am convinced my Knop reactor is failing to maintain STABLE Alk and cal. levels because the sps aren't growing as fast as they could be. Im also concerned that my reactor size now isn't big enough for the grown-in/higher demand for calcium..bigger corals, lots of coralline etc... For these reasons, i am considering upgrading to a CR2 Dual reactor with capacity for 14 lbs rather than 3.3 lbs, and also for its ability to maintain CONSISTENT effluent drop rates, my most important concern... I think the original Knop C was a "first model breakthrough" reactor at that time 1991? and we have much better more reliable models & custom makes on the market today. At the time of purchase.. 1 year ago, i had never fully and completely understood how they worked and this was my first attempt with A reactor...makes sense i guess... Since then maybe i have discovered flaws and reactor necessities as well as the essential demand for cal. and Alk. stability for sps. <Mmm, well: http://www.aquadirect.com/store/product.php?productid=21026 appears to be a substantial unit... I don't like the tops/fill-empty closure mechanism... those white screws... a pain... And I would take a read around the BBs re this unit...> Reasons for upgrade: 1) Reactor chamber too small (3.3 lbs) <Is too small for your system/application> 2) Knop C effluent dropper very inconsistent/unreliable <Likely mostly # 1) above and who knows what used as substrate (not real Korallith?)... perhaps purity of CO2...> For these reasons I am Saliferting and making adjustments to cal. Alk. EVERY OTHER DAY!!!! AGGH!! <No fun for sure> Hopefully I can test each ONCE A WEEK, right?? and not have to make major adjustments because i will hopefully have STABLE values...? <Yes> You thoughts on the matter are appreciated. Thanks for your time, Matthew <Mmm, for the sum of money et al. what's involved, I'd instead go with the AquaC unit: http://www.proteinskimmer.com/Product%20Pages/RX-1.htm Bob Fenner>

Calcium Reactors, brand/sel.  4/16/07 I'm in the process of researching a calcium reactor for my 550 total volume reef tank.  This is my first calcium reactor since all my previous tanks were smaller and I never had any difficulty keeping my calcium and alkalinity up.  My setup will be a mixed reef (no surprise) with 80% softies/LPS and 20% SPS.  I have always trusted the opinions of the WWM crew so I figured I would ask a question and I did search your archives but I did not see any mention of the three calcium reactors I am looking at.  The three models are the Deltec PF601S, Schuran Jetstream 1, and the GEO 818.  What are your thoughts on these models and if you think of another model I should look at please let me know. <Mark, I'm not familiar with using these products.  I can say that Deltec has a good reputation.  You may also consider the Knop reactors which I believe work very well.  My suggestion to you would be to post this question on our chat forum under "Equipment And Dry Goods".  Here is where you will get opinions from people that are/have used these products.   Go here:   http://wetwebfotos.com/talk/> Thanks <You're welcome.  James (Salty Dog)> Mark Crist

Hang on Calcium Reactor   03/23/07 Hi guys, <Hello.>            Thanks for all the help in the past. <Welcome.> I was wondering if there was a "hang-on" calcium reactor that you recommend. I do not have a sump so I need something that can hang on the back of the tank. I have seen a few but wanted to know what you guys thought was the best. <Try shooting Andy at "MyReefCreations" an email, I believe he has a few that can be modified in this fashion, while I don't use his calcium reactors, have been pleased with his other services in the past. I'm not sure if Knop makes a hang on reactor but if they do consider them as well. And while I don't like to name brands I don't like, there is one that rhymes "'orallin" and begins with a "k" that I'm not to fond of...I think Bob has shared similar sentiments on that one before.> Thanks, <Welcome.>    Jeromy
<Adam J.>

Calcium reactor on EBay???? I was wondering if any of you guys heard anything about these calcium reactors by Acrlicity on EBay? Here is a link: http://cgi.msn.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=4319334586&ssPageName=STRK:MEWA:IT Thanks for you help. Sincerely, Brian Marotta <Don't know the company... and do like the clean-ness of the acrylic and PVC work, the use of true unions... but NOT the tops of the reactor chambers being secured with those nylon screws! They are a pain to do, re-do, and often break off. Bob Fenner>

Calcium Reactor reviews 8/19/05 Hi. Are there any bad reviews on ReefTek calcium reactors? David <Hmmm... as much as I hate to refer our WWM friends elsewhere, we don't review products or see many reviews here. One of the big discussion forums is really the best place to find this kind of information.  I would suggest www.reefcentral.com, www.reefs.org or our sponsor www.reeffrontiers.com  Hope this helps!  AdamC.>

Calcium Reactors/Selection   4/28/06 Hi everyone, <Hello Marc> Hope the weather is good on your side of the world. <Not too bad today.> I am emailing to ask some advice regarding calcium reactors. Firstly in Australia there is a distinct lack of choice with reactors so I am ultimately bound by that limitation (unless I look to the UK - similar voltage to Aus) but the first question I had is what are the major differences and what should I look for when purchasing a calcium reactor (an open ended question I know but some incite would be greatly appreciated)?. They are a relatively expensive initial investment and I would like to get it reasonably right. I have identified two popular brands in Australia and would like any feedback on their performance or any experience you may have had with them. They are the Korallin C1501 (I think it is a 1502 in the US - 110v) and the Aquamedic 1000 unit. <If it were my choice, I'd go with the Korallin C1501.  Have heard good things about them and are easy to work with.  Keep in mind that I'm not saying the Aquamedic isn't a good reactor, just that the Korallin would be my choice.  Do google these if you haven't already and look at the features for each individual model before making your choice.  Do read the posted link here to aid in your decision.   http://www.wetwebmedia.com/calcreactors.htm> Also I would like to pass on that I recently installed a refugium on my reef tank after reading through the many posts on your site and I hope to see some payback in the near future once it establishes itself. <You should be rewarded.> Thanks for the great site and all the best. <You're welcome.  James (Salty Dog)> Marc

- Calcium Reactor Selection - Hi, I've been reading about calcium reactors and haven't been able to find reviews from folks who have used them.  I'm looking at K2R, Precision Marine, Knop and Korallin.  The Knop (S-IV) and Korallin(1502) packages are about $200 dollars in difference  Like I say I haven't found a lot of useful information.  Which one is the best to buy? <My personal favorite is the Knop S-IV - have used this reactor and find the design the most simple and elegant.> Also, what should I look for when buying a good reactor? <Lack of delicate parts - one of the best ways to maintain a calcium reactor is to give it a good shake once a month, so you don't want parts that are going to snap off accidentally. Likewise, a lack of metal parts is also helpful - the saltwater environment is corrosive enough, but the area inside the reactor will be a low pH, and even more corrosive so... even stainless steel parts are suspect - and that includes pump internals. Eheim pumps have ceramic impeller shafts so there's something to look for.> Are there any extras that I should know about like additional pumps or ph controllers? <Give this article a read, should cover those bases: http://www.wetwebmedia.com/calcreactors.htm > Thanks, -Brent <Cheers, J -- >

- Calcium Reactor Selection - Wow, thanks for the lightning response !. A follow-up question... How would you rank the following reactors overall...(I know you favor KNOP in the WWM pages)...Art's K2R; Precision Marine; Knop; MTC; Korallin. I look for efficiency, and ease of use and overall best piece of equipment... Thanks a bunch! <Yeah, I do like the Knop products, the S-IV is my favorite, mostly because it is an elegant design, simple to use and maintain, and efficient.> Dan <Cheers, J -- >

New calcium reactor hey again, hope everything is going swell for you guys. <<Hello, my day is going well so far... how are you?>> I'm looking forward to checking out the new reef shark tank at the John G. Shedd Aquarium in Chicago, have you heard about that? <<I hadn't heard.>> Do you plan on visiting it? <<If I find myself in Chicago, for certain, yes.>> Anyway to my question, I am thinking about dumping the Kalkwasser idea and investing in a calcium reactor. good or bad? <<Good plan, although putting some Kalkwasser in from time to time, even with a calcium reactor, is a good idea.>> Preferably a Knop. <<Good choice.>> My tank is a 90. Have you any info for me on the Knop "C" , would that be perfect for me? <<I don't have any info 'for' you, but I have used this reactor myself and think it is an excellent, and simple package - would be perfect for your tank.>> And have you heard anything on that new one called the "S IV" with the pump and bubble counter inside? <<Yes I have, is the reactor I am using now on my 180.>> Really could use some direction here in choosing. <<The S-IV is probably too large for your 90... both are excellent calcium reactors, but the Type-C is your best bet.>> Also would you keep filter pads in the "Tidepool" sump? <<Sure.>> or is that just a nitrate factory? <<Actually, the wheel would be the factory... you are supposed to take out those pads and clean them about every one to two weeks. If you don't clean them, then yes - they will become factories for all kinds of bad things.>> My nitrates are about 20, "Salifert kinda hard to judge" Tank has been cycling for about a month with about 95 lbs. live rock. <<If you have a nitrate reading of 20, then your tank is now cycled. If you do pick up that reactor, please read this article before you set it up: http://www.wetwebmedia.com/calcreactors.htm >>  thanks , I know you will steer me right. Jaime <<Cheers, J -- >>

Calcium reactors Gentlemen, how are you? <Very well, thank you!> Here is what I've run into. I was just about to purchase a Knop calcium reactor for my 90 gallon and I am told they no longer sell them in the good old USA. Is this true? <Completely false! Bob's wife, the lovely Diana, is a/the importer of Knop products into America.><<Mmm, no longer. Oh, still the wife, not the distributor for Knop in N. America... RMF>> And why? I am now looking at different reactors and don't really trust anyone but you guys. Everyone else out there is saying different things about different reactors. I was told the Aquamedic was a good one by one person, and another told me that the Aquamedic was not so hot and he liked the Precision Marine. <I am sure if you ask around enough you will find opinions for and against every make and model out their.> Maybe you guys could help me decide. I kinda would like a smaller footprint. Does Mr. Knop have some kind of special return of his reactor? <I think you mean the return of the line to the US and not the return of the effluent from the reactor. They are available. Several of our sponsors carry them.> Modified? <There are new models available now.> Something different that I might want to hold off on the others and wait for the return of the Knop brand? <Keep looking around, gathering opinions, and make an informed decision.> Thanks, Jamie <You are welcome. -Steven Pro>

Calcium reactors gentlemen how r u ? Here is what I' ve run into. I was just about to purchase a Knop calcium reactor for my 90 gallon and I am told they no longer sell them in the good old U S A . Is this true? and why?  <Umm, actually are still being sold... site: http://www.knopproducts.com/ May seem biased... but the N. Am. distributor is Diana Fenner (we're related). Great products... well-engineered, constructed...> I am now looking at different reactors and don't really trust anyone but you guys, everyone else out there is saying different things about different reactors. <Like? Here's our recorded spiels: http://www.wetwebmedia.com/calcreactors.htm and the FAQs files beyond> I was told the Aquamedic was a good one by one person, and another told me that the Aquamedic was not so hot and he liked the Precision Marine. Maybe you guys could help me decide. <Mmm, better for you to sample more "end users"... through the BB's like Reefs.org, Reefcentral, ours: http://wetwebfotos.com/talk/ and others for folks who have more hands-on experience> I kinda would like a smaller footprint. Does Mr. Knop have some kind of special return of his reactor? Modified ? <I'll refer you to Di (I don't know)> something different that I might want to hold off on the others and wait for the return of the Knop brand??? thanks Jamie <Good questions... I'll also ask Jas.C to chime in... oh, and Antoine as well... they have units. Bob Fenner>

Re: Anemones, Calcium Reactors, etc. Thanks for the quick reply Anthony!  I have 1 Hammer coral, 2 bulb tip anemones, and one large carpet that is quite happy.   <ahhh... yes, my friend. The two anemone species are especially problematic. We get buried in e-mail on issues around this. All seem to look good for as much as a year. In some cases towards two years. Almost none will make it beyond 2 years (allelopathy). The carpet will overwhelm the other anemones and many of the coral by then. Extremely noxious> It is attached to a rock and the bottom of the tank.  Any ideas to remove it without ripping it's foot?   <yes... many ways. But have some rubble (small and loose) piled near to its foot/base. Then shade the light directly above the anemone with a small ceramic plate/dish or like safe obstruction between the light and the water surface. This is an easy an gentle way to move most anemones (they will crawl onto the rubble  and into brighter light).> Also are the Fiji plate corals in the tank, are they considered LPS?   <yep... very hardy and easy to propagate keep... but extremely "hungry". They are less than 80% satisfied by the products of photosynthesis under the best lights. More than 20% of daily carbon needs to come from target feeding. This animal needs fed almost daily in aquaria or it starves in less than 2 years (most in less than 1). If fed... they are incredible! Hardy and fun> Should those be removed also? <Hmm... its not a pure science. All corals produce some amount of chemical defense. We are best to simply minimize unnatural aggression. 2 LPS in a tank of SPS is no big deal... but 10 is too much. How can we satisfy corals collected in 40-60 foot of water (LPS) with others collected in less than 10 feet? Not in the confines of a 24"tank under standardized lighting. Some fare well while others suffer in time> Thanks for the "heads up" about chemical war between the animals.  I will remove the anemones and the LPS this weekend.   <definitely the anemones ASAP. By themselves in a sunlit window would be magnificent! Think of a 60 hex with only that big bad carpet anemone in a southern window and a dozen humbug damsels playing in it!? Wonderful> About the calcium carbonate, I do add the B-Ionic but have never shaken the container before doing so.   <Aieeeeee! My ears <G>> Only at first when I received it. Could be my culprit.   <OH ya! Its a big problem. The ingredients are all clear but separate in the bottle and get dosed imbalanced (you can actually see the separation if you let the solution set over night in a clear graduated cylinder... looks like a thermocline)> I like the Knop C reactor also but the Korallin C 1502 might be better when I get a 180 gallon tank in the future.  Any thoughts on the Korallin models?   <no strong preference for any brand by me. I like Knop for their longevity and reputation. Some aquarists do not favor its smaller size. The new dual chamber Knop reactors are pretty sweet though! Have you priced them at Di's place yet? General Aquatics?> For such a pricey piece of equipment I don't want to buy a second one, if you know what I mean. Thanks for all the help! Brad Stefanko <Agreed... best regards, Anthony>

- Calcium Reactor Selection - Hi Bob, <Actually, JasonC today...> I just built a 180g SPS reef tank with 100g sum, and I'm looking for a Calcium Reactor.  Could you tell me which one is the best for me? The Knop model, the Aqua Medic model, the Advanced Reef model, or the Marine Life model. <Personally, I don't have much experience with any of those except the Knop reactors, which are excellent.> Thank you. Khanh Do. <Cheers, J -- >
Re: Calcium Reactor
Hi Bob and JasonC, <Hello...> Thanks again for replying to me so quickly. <No problem.> About the Knop Calcium Reactor, as I know it has two models, Knop-C and Knop-HD, which model should I choose for my 180g reef tank? <Actually they have more than that... four or five I think.> I think about Knop-C, but I don't know exactly how big of a tank it can handle. <The type C is rated for 180g... but you previously mentioned a 100g sump - your system is 280g, must fit the reactor to that.> I did some researches but each company said a different thing??? <Some are more conservative than others.> So could you tell me about the Knop-C please? <I would go for their new reactor, the S-IV [that's the Roman numeral four] which has an integrated bubble counter and pump inside the reactor. A very nice package with a small foot print. Would certainly be more than adequate for your system.> Thank you, Khanh Do. <Cheers, J -- >

- Calcium Reactor Selection - Korallin 1502  vs. Knop S-IV......    Is it worth the expense of going with the 10 Gal C02? <It's your money...> How long does the 5 gal last on a 135 tank chock full o coral & clams??? <Hard to say exactly - I would guess a 5lb tank would last at least six months. I use a 10lb tank and wasn't able to empty it in a year.> The Knop advertises it's for 150 +....that's cool for a 135 tank? <Yes, that's fine.> Also, on the subject of Controllers, to save time searching, if I'm not gonna use OZONE, do I need an ORP probe? <Not unless you just want to know the number...> Can the Aquatroller II measure KH or some factor of it using the pH probe? <Not that I am aware of.> What do you use a conductivity probe for?  Salinity? <That is correct.> Thanks again <Cheers, J -- >

- Calcium Reactor Selection - Good people of the Wet Web, <Good morning, JasonC here...> After reading for endless days, and reading contrary information, I am just gonna get all the equipment now and be DONE with it.  After digging around for days and only now finding that I shouldn't be using a wet/dry on a reef system (after I already ordered 1) I will just remove the media from it and use it as a sump, skimmer and a place to put a calcium reactor.  After already bugging everyone about everything else, I now bug you about your opinions as to worthiness and ability or the two following pieces: - Korallin C-1502 <Is a worthy piece of gear.> - KNOP S-IV <Is my favorite of the two - I own this model, and is my favorite Knop reactor, much more simple than the others.> The Knop is more expensive by about 70-80. <In my opinion worth the money.> Does one have some feature the other doesn't? <Not really, just a good design.> Is one more efficient than the other? <No.> And finally, can they both be used in the sump rather than divert pressure from the return line? <I'm not sure I follow - water has to be forced into the reactor somehow... just placing the reactor in the sump will not be sufficient. You have three choices, a small dedicated pump, a t-fitting off the main return pump, or a siphon from the tank. Where you actually place the reactor will make little difference.> Thanks amighty! p.s.  I'm an empirical kinda guy, wouldn't it be easier for those setting up an aquarium to have access to the most accurate data available, that is to say that after the tests are run on equipment and resulting conditions are known, can't we just publish the data and go "HERE, I TOLD YOU SO!  THIS METHOD (OR EQUIPMENT) HAS PROVEN TO BE THE BEST FOR GETTING THE DESIRED RESULTS, PUBLISH IT AND SPREAD THE WORD AS GOSPEL!!"   end of discussion. <Every situation is different - it's best to tackle them individually - what works for one will not necessarily work for all.> Live from dream world, Toilet Tank <Cheers, J -- >

Calc Reactors Hi Bob, <Author/friend Anthony Calfo in your service> I met you a couple of years ago at a marine conference in Ann Arbor, Mi. (Weber Inn). <Hmmmm...perhaps I'll have the same pleasure. I'm one of the speakers this year (March 23rd) same place and conference> You may remember the conference by a gentleman exclaiming the benefits of magic mud. Never bought into that idea.  <I agree essentially> You did mention to me that you highly recommended a calcium reactor.  <very much agreed! In fact, I like a second media chamber in-line to boost the pH of the effluent, etc> Well now a couple of years later I am looking into the idea. Before I purchase one though, I thought I would seek out the advice of an expert. I am looking at the Knop C and Precision Marine 422. Any thoughts on which one you might prefer? <merits to both indeed and fans of both abound. I personally don't have a strong brand preference.> Thanks in advance for any info, <if you haven't done so already, please read over the new bit from WWM crew member Jason C. at http://www.wetwebmedia.com/calcreactors.htm > Brian V. Grant <kind regards, Anthony Calfo>

Skimmers & Calcium Reactors I am in the process of setting up a 180 reef tank and need to get a new skimmer. The skimmer I currently have makes use of an external air pump and bubble stone, which I don't think will be anywhere near good enough for my new system. After reading through all your FAQ's and articles on skimmers, I've narrowed it down to 2 choices, the ETSS Evolution 750 ($344 w/pump) and the Berlin Classic ($169 w/pump). It seems that both of these skimmers will handle my tank easily, and from what I have read both do a good job. Is the extra $175 for the ETSS really worth it? <I would not recommend either. There are far better choices, namely Euro-Reef and Aqua-C.> Am I correct that both these skimmers will work GREAT with my 180? <I would say marginal.> Are there any maintenance issues that should effect my decision? <The Euro-Reef is incredibly easy to clean.> The same goes for calcium reactors. There are many good ones out there, all with good reviews, but there is a $70 price difference on the 2 that I am leaning towards, the Knop C ($249) and the K2R ($419). Any preference for the 180g? <Both come with Eheim pumps. The K2R is a good bit larger, capable of holding more media, which means it will go longer before needing opened and added to. Either will serve you well.> Any advice is greatly appreciated. Will <You are welcome. -Steven Pro>

RO Water Top off & Calcium Reactors Bob, <Steven Pro in this morning.> I top off my tank with water directly from my RO unit on an automatic system utilizing a solenoid. Do you have any advice on how to keep up with buffering as adding it has created spikes due to the automatic replenishing of fresh water and the fact that I only buffer weekly. Any advice. <This is really not a good idea. While it maybe convenient, it is always best to hold and aerate any demineralized water for 24 hours. This maximized dissolved oxygen and off gases excess CO2. It is the CO2 that is messing around with your alkalinity.> I also was considering purchasing a calcium reactor from Lifereef. Have you heard of their products. Any comments. <Have not used there products. Do solicit comments form other hobbyists on the message boards. I know of two very friendly boards; ours at http://wetwebfotos.com/talk/index.jsp and a friend's at http://www.thesea.org/forum/default.asp You may also wish to inquire at both reefs.org and ReefCentral.> Thanks, Liz <You are welcome. -Steven Pro>

Calc reactor for 120g Reef I am torn between the Knop model C reactor and the Korallin Kalkreactor model C1501.The Knop is about $100.cheaper if that means anything. Korallin says that a PH controller is not required as there is no chance for the non- dissolvable excessive CO2 to escape in the system unlike ALL other brands and is the most maintenance free setup in the world! Do all other reactors need a PH monitor.  <It's a very good idea> I would appreciate your comments on what Korallin states and your recommendation. <Have seen both, know the Knop product... and know it to be reliable> Also i plan on have mixed animals in my 120g reef ,soft, hard coral, and clams. metal halide /power compact. I have been told that I will need MH250watt/10,000K w/PC 7100k.What do you recommend and is there a brand preference? Thanks >> This lighting mix is fine... no brand/manufacture preference... the actual components are made by very few companies... most everyone has learned how to "put them together", do the sales, distribution.. . Bob Fenner

Calcium Reactors <Thanks again, Bob. Do you have any preferences on a particular manufacturer of calcium reactors? <Not much... DIY ones are about as good as the makes/models that one can buy off the shelf... Knop and K2R are the big winners currently in the U.S.... they will be supplanted soon. Bob Fenner>

Calcium Reactor.... Hi Bob, I have an under-sized Knop Calc reactor for my new 300 gallon reef tank. I used to use it on a 135 tank. I want to purchase a new reactor. On your WetWebMedia site you indicate that Knop and K2R reactors will be supplanted. New models or better manufacturer?? I would like to get a reactor soon, but want to get the right one as they are costly. <Don't know re the status of K2R, but Knop has just come up with a new model... and they do have larger sizes already. I would look to the "next size up". Bob Fenner> Thank you for your time. --- Dave Mart

In Search of Enlightenment re Calcium Reactors Hi Bob, Sorry - for forgetting to include those numbers in the first email. Bob my head now hurts. I've been trying to read as much as I can to make an intelligent choice on a calcium reactor. Then I happened on: http://www.marine-monsters.com/front/products/kalkreaktor.html <Great folks here> Now there are certain things I have held hard and fast to. One is not using any brass in a reef tank for brass is an alloy containing copper. Why then does this unit have a "brass check valve"? <Not to worry... it won't come in contact with the water... you'll see soon enough> Maybe you could just end my agony and say "Marty, buy a ______"
Re: A Search of Enlightenment re Calcium Reactors
Hi Bob, I really must thank you for motivating me to do more research. I have now visited many e-tailers sites (more than I'd care to admit), and read everything I can find (in english) on the web and in NG's. I have come to the conclusion that while there is a lot of pro calcium reactor sentiment out there, the big cost savings seems to be mis-information. Buying consumables for a calcium reactor instead of additives will only save me about $10-20 per year. In contrast, purchasing a calcium reactor, regulator, media, CO2, will cost me between $400-600 depending on brand/e-tailer. I understand that I could DIY for less, but getting all the pieces just right could be a nightmare. This does not seem to me to be a good investment. BTW, I did find out why a brass check valve. <Hmm, would like to see this analysis... counting health/vitality of your livestock? Check valves don't need to be of brass construction...> Thanks for your time and guidance, Marty <Many paths, many roads, many destinations. Which will you choose? Bob Fenner>

Opinion? (DIY Calcium Reactor) Hi Bob, What is your opinion of: http://homestead.com/geosreef/reactor.html Thanks, Marty <Looks like a nice, inexpensive home-made unit... with some good concepts (like single pass) and a cheapy "ramp clamp"... Would like to see some plastic clamps on those polyethylene tubing to PVC fittings... and a large funnel for loading the feeder stock in those columns... worth a try. Bob Fenner>

Re: Search for a Reactor, oneself Hi Bob, Well okay. Maybe I need to think some more. I DO want to do what is best for my animals, it's just a question of return on investment. I have checked into the following manufacturers of reactors: Precision Marine, ADV K2R, KNOP, Marine Life Aquatic, Aquamedic, Korallin, Reef Concepts, Canreef. <Quite a review!> While I can find some positive feedback for almost all of the above reactors (I wonder how much was written with a vested interest) <Assuredly, most all...> I have also heard and read that they all perform their task equally well and I should go with the least expensive. I have also read that the CO2 regulator is more critical than the actual reactor in terms of advantages of one brand over another. Your thoughts? Marty <Function the same? Not agreed here... do look for features like the size of the reactant canister, ease/mechanism of getting into it, changing media... needle valve quality, pump quality (get/use an Eheim...)... and finally, just like Dale Carnegie used to write, set a date for deciding (as in nothing is decided till it's done) and buy the better of whatever make/model you find superior... No need to agonize here... keep this issue in perspective... If you were buying a major appliance, like a refrigerator, you would/should give the question the same consideration... features available, utility, cost of acquisition, operation... about, say a thousand dollars worth... More consideration for a car let's say, even more for a home purchase... Affairs of the heart, let's not get started... My point, I sense you are sublimating here... settle on a good choice and be satisfied my friend. Bob Fenner>

Ca Reactor Hello again! I've been fighting all week trying to keep the Ca levels up, and it's been a losing battle. (The Calc/water mix I was pouring into the prefilter box clogged the prefilters, and probably somewhat has clogged the biofilter on the DAS system- <You begin to understand my disregard for such "supplementing" practices...> -on the good side of all this, when I was cleaning the prefilters last night, I found and removed a rusty razor blade that some bozo had dropped in the filter box at some point--I bought this tank used and the blade had probably had been in there from the time it was set up. . .) <Yeeikes... good find/removal... > Based on my experience of not finding a practical way to get Ca into the tank, a Ca level that drops about 30 ppm per day, and not wanting to try to become an "expert" in the hazards of dripping Kalkwasser, I WILL have a Ca Reactor by next week. <Yay and Alleleujah! You won't be disappointed... being the "detail" person you are... you will appreciate the tremendous ease, use, safety of this device> I'm not really fretting over what kind to buy, except that it will be recirculating and have an Eheim pump. I'm considering the Canreef, as it looks relatively simple to service and do media changes and has a nice capacity. Also considering K2R. <Don't know the former at all, the second is fine... and have you looked at the Knop line? Try a read through the offerings of the folks companies listed on the Links Pages/Business on the WWM site> I do have a couple of questions about accessories, however. First, solenoids. If you don't have a solenoid on the CO2 regulator, and there in fact is a power failure, what will happen when the power comes back on? <Nothing... they "fail" and "stay" off... (I guess I should say "ideally"... as these electromagnetic switches can fail as well...> What happens if there is a CO2 "overdose"? I'm just trying to find out what I really need. I've found solenoids for $45 or so--so it would either be "cheap insurance" or an unnecessary expense. <There is a wide range of "safety" margin in using these devices... not to worry you, once you establish the needle valve, flow settings there is little that does go awry> And as to the pH monitors that are recommended by you in the FAQs, how are they utilized? Just to monitor pH in the tank, or the effluent, or both? Or are they somehow rigged up to control the flow of effluent or CO2 out of and into the reactor? <Both... need to address many, MANY sections, parts of the WWM site... but these probes can be coupled with on/off valves to deliver more effluent, CO2... I don't use them myself for such... but do rig same up for other "farms", holding facilities... and do use electronic meters for "just testing" water qualities> Thanks again for helping me to sort through all this stuff--my tank inhabitants will be all the more happy once this stage of progression is completed. . . <A pleasure> P.S. RE: the dead plate coral--ammonia, nitrite and nitrate all tested "0" again by the next afternoon. Thanks for "holding my hand" on that one. . . <Ahh, good... as expected> One other question--which may fall into the "stupid question" category. . . <Assuredly, there is no such thing> I believe the biofilter is somewhat clogged, because even after cleaning the prefilters, I'm not getting as much output from the main powerhead as I was previously. Is there a safe way to clean particulate matter from the biofilter media?  <With it up and going on the system? A chemically inert rod (wood, plastic) to "stir it up" gently (half one day, the other half another)... and with the system apart? To gently rinse with white vinegar (dilute acetic acid) and rinse, drain, rinse, drain, add more calcareous media, replace on system> (My guess is that it should be completely left alone. .but more harm in not asking than in asking. . .) Can the biofilter media be "dipped" in system water without destroying or substantially impairing the nitrifying bacteria? (By "system water" I don't mean in the tank, but water that has been siphoned off during a water change.) If this is even possible, I wouldn't do it for several weeks, since the prefilters were just cleaned thoroughly with RO/DI water and any nitrifying bacteria that may have been in the prefilters "helping out" with nitrification will have been rinsed away. <Always a risk possibility... But in systems that are otherwise "cycled" and stable, there is much nitrification going on elsewhere... such that one rarely sees/detects a difference> Thanks once again for your expert and honest advice. <Anytime my friend. Bob Fenner> James A. Deets

Re: Ca Reactor http://www.canreef.com/careactors.htm  FYI--Here's a link to the Canreef Calc Reactor page. I actually found out about this model by reading the FAQs on Calc Reactors on your site. You commented that you didn't like the thumb screws/o-ring closure. <Ah, yes... still don't like these traits> But it seems like a pretty simple setup that's practical--i.e., self-filling bubble chamber, no feed pump needed, about $50 more than the lowest price I've found for the Knop C but much less than others. (I read on some web page selling the Knop that the Knop C requires a separate feed pump--although that doesn't make sense and has to be incorrect, as a siphon (or pressure differential in the recirculation plumbing created by the action of the recirculating pump) should allow system water to feed into it. . .) <Yes, though folks do use a separate pump to good advantage> I'm sure I'll have plenty of questions as I get this all going. . . Talk soon. <Be chatting then. Bob Fenner>

Calcium Reactors Hello Bob, How are you? Hope all is well. I just finished reading your book (The Conscientious Marine Aquarist)...great book by the way! Wondering if you will write a book specific to reef aquaria only (will definitely buy!)? <Have written most all of TCRA... waiting (and WAITING) on a/the publisher... intend to have the new alliance of Microcosm/TFH produce, distribute, but they are busy... with other projects...> I am in need of your expert opinion/knowledge regarding calcium reactors. I am having difficulty deciding between the Marine Technical Concepts (MTC) Mini-Cal reactor or the Knop C reactor. I have done primary and secondary research about the two reactors, and found pros and cons with the two. <Me too> Fortunately, there are numerous publications/personal experiences available for Knop, and I have seen both products in person. I definitely found significant differences in terms of construction/structure and ease of setup between the two reactors. The MTC reactor appeared to be vastly superior in craftsmanship/sturdiness, MTC does not require any additional plumbing...while the Knop requires a return pump and additional pumping, MTC runs on an Eheim pump...similar to the Knop, MTC have dual media cylinders...second cylinder removes free CO2, and they both are relatively similar in terms of maintenance...although MTC use a lot of nylon screws for the top cover (which require a little more work and care) vs. Knop use one screw.  <Very much agreed here... and these screws are a source of real, make that HUGE trouble... when will our interest learn of other easier, more fail-proof opening/closure mechanisms... like the pool/spa filter industries...?> Moreover, the difference in price is $50, MTC being higher. However, my concern/question is the efficacy of the MTC reactor (unable to find much information regarding this product, unlike Knop). So I decided to visit the folks at MTC and asked about their product and various biomineral parameters pertaining to their reactor. They informed me that the only parameters I should be testing is tank pH, output effluent ~ 20ml/min, and dKH ~ 12...all other biominerals are insignificant (calcium, magnesium, alkalinity, etc.)!---Is this true/accurate?  <What? Not as this is written... of course the alkaline earth materials are important (we could/would call these "dKH reactors" otherwise...). Perhaps whoever related this to you meant that "it is best to measure flow and dKH" as indicators of appropriate use?> I questioned their statement; if the sole purpose of their reactor is to build/maintain dKH, and all other biominerals are irrelevant, then why call it a calcium reactor, why not call it a dKH reactor?  <Oh, oh, we're starting to think along the same lines... what are we having for lunch today Anywho?> If dKH is consistently high, and calcium is consistently low, isn't it an imbalance of biominerals? <Possibly...> Or does a consistently high/stable dKH ultimately center/balance all other biominerals through time/use?  <Depends on a few factors... what you're melting down, what is being taken up, dropping out in the main system...> Is dKH the single most influential factor with regard to a calcium reactor (that is how the folks at MTC make it appear to be)? <IMO, no... one of a few important variables that can be measured to access the system, reactor... I would, do measure dKH AND calcium in our effluents and systems... and pH at times... and am not concerned generally with the dKH being this high, but more so with calcium dropping much below 350ppm... and staying there... in our mini-culture facility (about 4k gallons, mostly hard and soft corals)> Something is amiss, and I am at a lost. Can you please try to clarify the relevance of dKH specific to the MTC reactor? I want a second opinion before making any decision. <I'm in the same club... will gladly "chat" with MTC's rep. on the topic... "If" they have a "standard" reactant that they back with experimentation behind it, a written warranty of how this material will "behave" in all reef/marine systems based solely on dKH measures, I am satisfied (though surprised)... as "all that could go on" in different set-ups with new live rock, plenums, copious growth of mineralizing life... would/could be trouble here. In point of fact, this "linear thinking" (A to B to C) is exactly why simplistic "Kalkwasser" dripping/pouring in is such a dismal failure...> Thank you in advance. Regards, Daniel <Am very sure we'll be chatting. Bob Fenner>

Carefully planning the expansion of my reef Hey Bob, So you have answered all my questions about refugiums and the like directly and indirectly.... I am NOT making the same mistake I made when I got into this hobby and just jumping in with little research :) <Plenty of time now... and more than enough new mistakes, omissions to make w/o revisiting the old ones> So before I set up a sump/refugium type deal I want to make sure I am solving MOST issues at once and not limiting my solutions by taking a particular path.... I want to make this reef a little more self sufficient. Already I see that adding chemicals, such as CA and trace elements will become expensive and a burden, worst I could neglect it and that would not be fair to the residents of the reef :) So that being said, I want a Ca reactor... <Good idea> I don't know if you are not permitted to give brand name recommendations but I am asking anyway :) <Yes... it (this site) is of my creation, origination... can/do say pretty much what I think, feel... a few brands are fine, Knop, K2R... and there is sufficient help to consider DIY... see the link to Oz's Reef on the WWM links page> I only have 20 inches in the refugium/sump to fit it... <You mean within the stand? An important consideration... some will fit... or you can place the unit outside of the stand, delivering the effluent via a line that drips into the sump> I am beginning to think that I will have no room for the refugium part if I put a skimmer and a Ca Reactor in the sump side. The tank will only be say about 10 gallons of water in a 20 gallon tank. I thought that I had room for a 27 gallon but then I would not have room to put my hand INTO the tank to do stuff.... I might get a custom one built to the maximum dimensions of under my cabinet... spent too much already to skimp now :) <Or perhaps a more flexible container and through hulls fitted with flexible tubing... Like a Rubbermaid tub?> Ok, So what Ca reactor will suite my needs with the space limitations and a 108 Gallon Reef tank. <Do take a read through a recent issue of FAMA (Freshwater and Marine Aquarium Magazine) and/or the manufacturers listed on the WWM links page here. I haven't reviewed what's available in several months> Other specs: 108 Gal 173 Lbs LR 160 Lbs crushed coral 5 Powerheads 440 Watts VHO Fish and inverts and corals (Anemone, Green brain, Colt Poly, mushrooms, Bubbles, etc) SeaClone skimmer I am dropping (well want to anyway) for a AquaC or other... again space restrictions... Euro-reef would fit too... So what do I need buddy (anything else?).... I want to get it right.... I guess everyone does.. that is why we write you :) <Just the gear that goes with the unit... a carbon dioxide bottle, regulator, needle valve, controller if you really want one...> But don't worry. I have not stopped using my own head and won't rely COMPLETELY on you... or will I, hehehehahaha:) <Now you're worrying me!> Kind regards, Robert Jackson of Canada.... Fun FAQ's Yes people use chillers in Canada too :) <Be chatting. Bob Fenner> and... Ca Reactor cont'd Hey Bob, I have to leave work and was too lazy to reopen hotmail :) How about this reactor... sounds impressive... C-1502 KORALLIN KALKREAKTOR Regards, Robert Jackson <Yes, a good unit. Bob Fenner>

Ca reactor Any recommendations on a small (possibly a hang-on-back) calcium reactor for a 45 gal reef. If not available commercially can one be made by a somewhat handy type of guy?  <Yes to the latter. Please peruse "Oz's Reef", site of choice for pet-fish DIYelfers: http://www.ozreef.org/> Cost is a big factor as I face immanent divorce if I keep spending money on this wonderful hobby. <More than worth the monetary cost for what such activity will save you in your sense of self-worth, involvement in the real world.> Much thanks in anticipation of your reply. Raul <I am with you my friend. Bob Fenner>
Re: Ca reactor
Thank you for you reply. I agree that this hobby does a lot for my overall personal well being. <Mine, definitely> I am a computer network guy by trade and many times contemplate how much happier I would be if I could work in the reef hobby for an occupation.  <Perhaps you could do a few installs, help folks service same... An easy job (and very enjoyable... I did this for nineteen years), with generally flexible hours, decent pay... As a side job.> Planning and maintaining my reef bring me much joy and even more important is the quiet calming effect which it has on me. It seems to make our hectic lives more complete. Thanks again for your comments and I will definitely check out OzReef. <You won't be disappointed my friend. Service to you. Bob Fenner>

Calcium reactor Dear Bob: I have a couple of quick questions I hope you can answer in your unbiased manner. 1: Are Calcium reactors as efficient as the seem in print? <Some are about all they seem to state... there is an enormous range of "cut and glue" versus scientifically engineered, well-constructed types... AND very importantly, the actual use/maintenance is an extremely large factor in actual function of many/most units... That is, if not "kept up" with replacing/shaking media, bubble count/effluent pH... the best, better reactors are no better than the worst.> Does the CO2, in addition to making the reactor carry out its primary function have any other benefits for the tank? <Many... most importantly to provide overall homeostasis chemically/physically, drive the light reaction of photosynthesis...> I dose my tank daily now and was looking an improvement. However, the cost of the average setup warrants some further research. <agreed> Any suggestion on a brand if you do advocate its use? <Knop... a paragon of excellence... Where to start here? I advocated (in person, en voce in the hobby press...) the use of foam fractionators for thirty some years (very lonely years back...), and calcium reactors for going on twenty... seeing them in use in aquaculture, in the "big" trade shows, principally the Interzoo every other year in Germany... And not the relatively toxic, expensive use of Kalkwasser... Look at the features on the seemingly simple Knop products: great pumps, solid components, direct, easy to reach controls. Their link: http://www.knop-usa.com/ Note I state, "look at their features"... an aquarist can build their own, and there are many other new models/makes by others... all worth considering> 2: I have a basic sump filter that I have placed some live rock in, I don't have any light source in or on it being that it's located under my tank stand, and of a material light won't penetrate. I was wonder if the rock can do its job and what would be the improvement if I do manufacture a new top and light it up. <Mmm, there are advantages even to unlit sumps of this sort... Or if so inclined, even "underwater" light fixtures available... I would modify the top, place a light, run it either reverse photoperiod with the main system (with a few hours overlap), or continuously> I also gather from your readings, that some tanks with refugiums in place have no mechanical filters in place. What polishes the water?  <The life in, on the rock, substrate, other surfaces> Do these types of systems work with fish in the reef tanks? <Yes> 3: How would a small sand bed do if I place it in the sump. By small, I was thinking of a 7"X9" Tupperware type container, 2" deep with live substrate placed within. I would then cover it screen of some sort to keep it contained. If that's the wrong approach, how could I improve it? <Some folks use deep sand beds, plenums, substrates in their sump/refugiums... some only live rock... depends on your esthetic desires, what you're hoping to achieve with such use... if you have a calcium reactor going you won't likely need/benefit from more biomineral, alkalinity... but if your livestock eat the sorts of organisms cultured in such material... Read through the Refugium FAQs here: http://www.wetwebmedia.com/refugium1.htm DSBs here: http://www.wetwebmedia.com/dsbfaqs.htm> 4: Final point. Why doesn't all the rock and sand in my display tank do the job of filtering and nitrate breakdown? <Can... given very little livestock, restricted feeding... but more stable, optimized to have more volume, more rock/sand... and alternating light/permanent cycle in an added sump where a lack of predators allows for other life production. It's full of the same life I see on the rock in the sump. <Ah! You have a good mind, discerning. Look into the Intel QX3 microscope: http://www.intelplay.com/products/qx3/ and consider what sorts of sampling, recording, enumeration you might do to test, see the "preponderance", abundance of life in both settings over time...> Thank you for your valuable time. You provide a fantastic service. Brett Manthe <You are welcome my friend. Thank you for asking, sharing. Bob Fenner>

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