Toxic tank, Contaminated Calcium Reactor Media    2/12/07
  I have had toxic tank syndrome for 8 months now.  My pulsing Xenia starts to turn black in less than 24 hours.  All SPS corals had to be removed from my 180 gallon 5 year old tank.  Lost some fish, scooter blenny, mandarin, Rainford goby.
<Yikes... so, what have you done re the toxicity?>
    To make a long story short, I changed water like crazy, searched everything for a metal contamination.  Could find nothing, so I emptied the system completely.  Cleaned it all out, replaced the sand bed, all rock, everything out, and refilled with natural sea water.  After a week, I put a piece of pulsing Xenia in last night, and this morning the polyps were starting to turn black.
    I got mad, again, and the only thing I had not done was to empty my calcium reactor.  I put the media in a bowl and searched it.  Using a magnet, I found small flakes of metal of some sort, laced through the media!!!!!!!!!
<Yikes...>
  I have not idea how it got there!  Not from me!  I won't mention a brand name here.
<I wish you would... My wife, Diana, used to distribute Knop Products in N. America... their Korallith was/is very pure...>
    I will do a 100% water change as soon as possible.  I can not afford to change the rock and sand bed again!  What further steps should I take?  Carbon?  Poly filters?
<Yes to both of these... this should do it>
Will my new rock and sand be ok?
<Very likely yes>
There are no fish or corals in the tank st this time.  All have been moved to other systems.
  Help
  Richard
<Thank you for relating your experiences... Will save many others huge headaches and grief. Bob Fenner>

Calcium Reactor - 02/11/2007
Hey guys, wanted to start off saying thanks for all the advice you have given me on my refugium setup for my 30gal mini reef.  The refugium is working nicely and I can see at least 30-40 very large copepods scatter every time I turn its light on (nice eh)
<Ah yes>
and the macro algae as grow so much in it that I had to pull some out so water can still flow thru. On to my question: I have been (not admittedly) been dosing my tank with alk/CA 2 part system and once and a while dripping some Kalk at night.  The tank seems very healthy and I am getting slow grow from the corals.  I wanted to kick things up a notch and also do away with mixing Kalk by adding a Calcium Reactor.
<A useful tool>
  The problem is I don't have a sump on the system and the refugium is too small to fit anything into it, can you recommend how I would set this up as to the fact that most of the systems I see go into the sump.
<Can be fashioned to "hang on"... best on the refugium>
A side question:  I get very small amounts of algae to grow on my rocks, that never get out of hand and seem to come and go with time.  The funny/confusing thing is that it ONLY seems to grow right at the base of the corals?
<Interesting...>
I have MANY square inches of rock space for it to grow on, it just seems to like the corals.  I don't like it because it makes the corals unattractive for a while, but does NOT seem to affect them, any ideas? Again thanks,  -Gary
<Mmm, w/o knowing much more re your standing water chemistry, am wont to make any speculations here. You can wade (literally for hours) through various similarly vague questions/responses archived on WWM re such issues, circumstances. BobF>

Knop Calcium Reactor Instructions - 02/06/07
I need to find out how to get instructions for a Knop s iv calcium reactor. Does anyone know how to contact Knop or have the instruction.
<Try writing to: Knop Products, 8586 Menkar Rd., San Diego, CA  92126
<<Actually, contact Marine Depot (.com) re... the U.S. distributor. RMF>>
or if you need some basic instruction, try a search here on WWM. this is a popular product, and there have been questions as to it's tuning and adjustment.
-GrahamT>
Thanks

A Ca reactor second chamber  2/5/07
I am running an octopus Cr 100 recirc calcium reactor on my 600 litre heavy stocked predominantly SPS system. The reactor is rated for 100 litre system (really dunno why reactors are rated for system volume and not caco3 consumption rates, but that for another day).
<Good>
The reactor is barely keeping up with my demand for calcium. I recently  molded two gravel siphons into an add on chamber for my reactor. It has the effluent from my reactor entering through the bottom and after passing through the media, runs past my probe and drips into the sump.
My alk reading of my effluent went up from 25dKH to 32dKH after doing this..... Not sure if its because of the new fresh media or increased contact time with aragonitic media.
<Likely a bit of both>
Should my pH controller be set at a slightly higher pH, as its situated in this passive reactor?
<Mmm... no... I would leave as is>
Will this second chamber increase my effluent (ultimately tank ) readings for Calcium?
<I would not be at all surprised it did so... at least at first...>
Would it be advisable to put a small recirculating pump on this chamber as well, as when i shook it tonight, i noticed a white powdery aragonite settlement at the bottom, which will surely be more beneficial in the tank than in the "reactor".
<I would leave this be as well... the "dust" will either go into solution and be distributed, or not>
Would really appreciate your input.
Thanks for your advice
IVAN
<Welcome. Bob Fenner>

pH Level In Calcium Reactor 1/23/07
Hello, and how are you doing. I have a simple question for you if you don't mind me asking. What should my ph in the calcium reactor be if I am using CaribSea calcium media. Thank you for your time, patience, and,  advice.
<Should find answers to your questions here my friend.  http://www.wetwebmedia.com/calcreactors.htm
James (Salty Dog)>
J.
Blue

Calcium Reactor Adjustment/Potential for Earth Element Overload – 01/23/07
Hi gang,
<<Hello Chuck>>
I just bought a Korallin 1502 calcium reactor for my reef. . .and am seeing almost immediate improvement in the health/appearance of my corals after an over-the-holidays stretch of having trouble maintaining calcium/PH.
<<Glad you found a solution to the problems>>
My questions are these:
(1) Since the aragonite media is being dissolved in pressurized-and CO2-enriched tank water, is it difficult (or preferably impossible) to create a 'snowstorm' effect as long as I don't add other tank additives which would affect alkalinity?
<<I think it unlikely as long as the reactor is not grossly oversized for the system.  In other words, if the unit was to provide calcium/alkaline material faster than the system could utilize it then there might be the potential for overload...though I can’t say I’ve ever heard of a precipitous event attributed to the calcium reactor.  But even so, these are not “install and forget” pieces of equipment.  You still need to monitor earth element/bio-mineral content and make adjustments to the reactor as necessary>>
(2) Are some of the other minerals (strontium, magnesium, etc.) which are in the media being released in bio-available form for use by the corals and other occupants of my system? (I've heard/read both 'yes' and 'no' on this.)
<<This stands to reason, yes...though content will vary with differing medias and all elements don’t have the same range/rate of solubility so who’s to say “how much” of the available elements in the media are being reintroduced.  As with alkalinity/calcium, these to need to be tested periodically and supplement as/if necessary>>
BTW, after a bit of trouble finding the right CO2 bubble rate vs. effluent drip rate for best effect on the smaller Korallin model, the tech guys at Marine Depot advised 15-20 bubbles per minute with about 60 drops of effluent. . .scaling it back a bit once the desired levels are reached.
<<Good advice this last>>
I bring it up only because it's not something that was in my owner's manual.
<<Thank you for the input>>
Chuck
<<Regards, Eric Russell>>

CA Reactors…Calculating Dissolution - 12/31/06
Good morning,
<<Hello>>
I would like to ask a question pertaining to the "Calcium Reactor without CO2? - 12/14/06" thread.
<<Ok>>
I have been considering the same thing as the original inquiry.  I have well water with a pH of 5.7-5.8 after RO/DI.
<<I see>>
I know enough chemistry to be dangerous, which is not much.  I seem to remember it would be possible to calculate the amount of Ca liberated by raising the pH from a given point to the point it will no longer react with the media.  The problem is I cannot find the equation anywhere.
Thanks
<<Hmm, don't know what that equation would be either...I'm sure Bob will chime in if he knows.  But so you know, the media will "react" at "any" pH level...it's just that at the higher pH more bicarbonate has been converted to carbonate leaving less "room" for the media to dissolve before reaching the point of saturation where the reaction stops.  According to Randy Holmes-Farley... "At a pH of 6.5, about 50 times less carbonate is present than in the same solution at pH 8.2"...  The difference here being the lower pH allows "much more calcium" to dissolve before reaching saturation.  Regards, EricR>> <There are solubility product constants... and I do believe/think that these can be calculated further for different pHs... the KOH for carbonates being? Perhaps a go with a CRC reference... or trip to a large (college) library, help at a Chemistry dept... Am out in HI, and too bushed from traveling to do much more than make these vague generalizations. RMF>

Re: Ca Reactors    1/5/07
thanks for the prompt reply.
any word from Bob.
<Mmm, strange you didn't see this... Please read here:
http://wetwebmedia.com/maralkfaq5.htm
about the third response down. RMF>
CA Reactors. Calculating Dissolution - 12/31/06
Good morning,
<<Hello>>
I would like to ask a question pertaining to the "Calcium Reactor without CO2? - 12/14/06" thread.
<<Ok>>
I have been considering the same thing as the original inquiry.  I have well water with a pH of 5.7-5.8 after RO/DI.
<<I see>>
I know enough chemistry to be dangerous, which is not much.  I seem to remember it would be possible to calculate the amount of Ca liberated by raising the pH from a given point to the point it will no longer react with the media.  The problem is I cannot find the equation anywhere.
Thanks
<<Hmm, don't know what that equation would be either...I'm sure Bob will chime in if he knows.  But so you know, the media will "react" at "any" pH level...it's just that at the higher pH more bicarbonate has been converted to carbonate leaving less "room" for the media to dissolve before reaching the point of saturation where the reaction stops.  According to Randy Holmes-Farley... "At a pH of 6.5, about 50 times less carbonate is present than in the same solution at pH 8.2"...  The difference here being the lower pH allows "much more calcium" to dissolve before reaching saturation.
Regards, EricR>>

Re: Ca Reactors  1/5/07
Thanks a lot.  I had been watching the Ca Reactor FAQ.  Anyway I am off to the library.
Bart
<Real good. Please do report back on your experiences, findings. Bob Fenner>

Is this normal? Knop Reactor...  1/5/07
Happy New Year WetWebCrew!  David here, and I need some help with figuring out if what I'm observing with my Knop S-IV Ca reactor is normal.
When I adjust the drip rate it effects my CO2 bubble rate.
<Mmm... a little maybe... there might be a pressure differential in the contact chamber that might allow this... but not much>
  I siphon from the top of the tank to the reactor sitting on the floor, and it fills just fine so no impediments there.  I start the CO2, and I only have a few frags, and about 175 lbs of LR in a 150 gal tank, and my bubble rate is already 130/BPM for an effluent of 6.7-6.8
<pH>
with a drip rate of 3 drops/sec.  This gives me roughly 8 DKH and 400 Ca and an overall PH of 8.0 - 8.15.
<Sounds about right>
But, if I adjust the drip rate lower it changes my CO2 rate lower.  My leather coral use to thrive when I was keeping my PH around 8.3 with Seachem additives, but has slowly shriveled up, and I'm assuming it is because of the lowered PH.  My effluent is 35-36 DKH, and my Ca is 500-520.
<Mmm... too high all the way around>
Maybe I have a bad solenoid or check valve?
<No... just a bad adjustment...>
I suspect there's some pressure in these units, but I didn't expect that it would do this.  
<Mmm, there is a simple means of limiting the pressure to about right... using the stock tubing provided...>
I've had the reactor for roughly 10 months, and this is the first time I've noticed it.
<Umm... likely something else going on here... either the concentration/purity of your CO2 and/or the media you're trying to melt down... You're using Korallith I take it...>
Also, can't maintain the same DKH and Ca values I once did with less CO2.
<Mmm, see the above>
  For example, I used to be able to keep the above values with 30 BPM, and a drip rate of 2 drop/3 sec's.  My bio load hasn't changed, so I'm wondering if the blue coarse filter pads at either end might cause a decline in efficiency over time if CO2 is only passing through parts of the blue pad even when properly rinsed?
<Not these pads... they last forever... ostensibly... Don't need replacing... just rinsing with the periodic refreshing/re-newing of the media>
I've tried different types of Korallith media, and tried 2 different CO2 bottles to find any particular source of inconsistency.
<Oh! Good>
Is there another type of media that is as good as Korallith media IYO?
<Nope, not with this brand, type of reactors>
My hope is (like everyone who has a Ca reactor) to be able to keep a PH of 8.2 to 8.3.  If I turn off my reactor at night, I would have an even harder time maintaining my current values,
<Mmm, I would arrange a timer, not run the reactor during dark hours here>
and I don't want to drip Kalk at night, because I tend to make mistakes with it.
<You and most everyone else>
  I don't have room for a refugium, and I can't use reverse lighting at this point.
What can I use to boost my PH without working against what's already happening with a Ca reactor?  
<Mmm, the simplest, safest way would/will be to add a commercial alkalinity booster... a part 2 of two part component product... something with sufficient carbonate... In/with your water change regimen. Bob Fenner>
Thank you,
-David Brown    

Calcium Reactor without CO2? - 12/14/06
Hello crew!
<<Howdy!>>
Long time reader, first time writer.
<<Welcome>>
My main question is, is it possible to operate a calcium reactor without CO2 injection?
<<Strictly speaking, sure...but it would be of little use/benefit to your system if operated in this manner>>
This occurred to me after measuring pH of my RO/DI water and it was 6.5.
<<...?  Are you thinking of flowing pure RO/DI water through your calcium reactor?>>
Does the carbon dioxide itself add alkalinity/provide a balanced calcium supplement or is the balance already present in the media that is used?
<<The purpose of the CO2 is to lower the pH of the tank water/saltwater used to feed the reactor to a level low enough to dissolve/render in to solution the media in the reactor>>
My thoughts were to dose some of my top-off water(6.5 pH) into a reactor via a peristaltic pump and back to tank.
<<Mmm, I think I'm getting the picture now...maybe...  If you are planning to do this to condition/buffer the "top-off" water on its way to the display this would be fine>>
Would this dissolve the media or is CO2 a necessary component?
<<The low pH of the RO/DI water will dissolve "some" media...but not like that in a "conventional" reactor setup with CO2 present to "keep" the pH of the water depressed>>
I currently use one teaspoon Tropic Marin Bio Calcium daily and dose Kalkwasser using a peristaltic pump for all top-off water and was hoping to add a balanced calcium method that does not carry with it the high pH of Kalkwasser or daily routine.
<<The calcium reactor fed RO/DI water will take the place of the Kalkwasser for "top-off" only, yes?  I don't really think this will give you what you're seeking...but is worth the experimentation to see for yourself>>
With Kalkwasser dosing (as much as 1 gallon in 24 hrs.),
<<Is all relative...how big is your system?  I dose 4-5 gallons per day through a Kalkwasser reactor>>
I often experience pH levels of 8.5, although no lower than 8.4, even at night; so very stable, but high(?).
<<Some authors (Anthony Calfo for example) would call this "perfect">>
The possible too high pH and daily routine are the only things that really concern me about my present methods.
<<I don't consider you pH a problem...and the "daily routine" could be lessened by using the peristaltic pump to dose the Kalkwasser through a Kalk reactor>>
I should say that the tank is a 50 gallon that inhabits SPS species and Tridacna clams and typically calcium is 380- 405ppm and alkalinity is 3.20-3.50 meq/L.
<<This is fine>>
I am simply trying to eliminate part of the initial cost of a calcium reactor.
<<Perhaps a Kalkwasser reactor is a better purchase for you then>>
Thank you in advance for your reply.
<<Quite welcome.  Eric Russell>>

Re: Calcium Reactor without CO2? - 12/15/06
Yes, was thinking I would continue adding perhaps 80% the amount of Kalkwasser top-off that I currently dose and dripping the remaining 20% or so calcium reactor effluent (made with RO/DI water) also.
<<Honestly mate...this seems like more trouble for any benefit you think you might gain from this.  I would simply use the Kalkwasser reactor and calcium reactor (in the manner originally intended for this equipment) in conjunction with each other>>
I have seen that it is common practice for one to do both Kalkwasser and calcium reactor nowadays,
<<...is what I do>>
however I'm guessing that a particular ratio of Kalkwasser/reactor effluent would be trial and error to achieve the desired results.
<<Hmm...the Kalkwasser reactor would produce based on the evaporation rate of your system...the calcium reactor (fed water from the display and employing CO2) would be "tuned" for optimum performance.  Whether or not your system needs/could utilize both depends greatly on the size/stocking density of calcifying organisms>>
I assumed that the reason one would do this, is to have the low pH reactor effluent and high pH Kalkwasser balance each other out.
<<No...the reason for running both reactors would be to utilize the particular benefits of each and/or provide for heavy calcium demands beyond what either can accommodate alone.  In addition to the calcium/alkaline buffers provided by both systems...Kalkwasser provides for precipitation of phosphate/heavy metals, saponificaton to assist skimming, and pH support by tempering organic acids (due to its caustic nature)...a calcium reactor contributes essential earth elements (depending on quality of media) to include strontium, magnesium, some major and minor trace elements, etc. absent in calcium hydroxide (Kalkwasser).  Arguably on an "average" system, both methodologies can be replaced with frequent partial water changes>>
I have also heard some freshwater tanks use calcium carbonate shells to increase hardness because they dissolve at the lower pH (?)/freshwater(?).
<<Many Cichlid systems incorporate carbonaceous material to boost/bolster pH, yes>>
This also made me wonder if CO2 may not be needed in a reactor to dissolve the media.
<<For the reactor to function efficiently as designed it will require addition of CO2.  What you are proposing for buffering you top-off water could be just as easily; and likely more efficiently, done by adding the reactor media to the RO/DI storage container...in my opinion>>
I hope I am being clear about my goal (?).
<<I think I understand, yes>>
I wasn't thinking of stopping Kalkwasser additions, just adding a bit of reactor effluent to knock down the pH a little bit and eliminate the daily routine of Bio-calcium additions.
<<Mmm...better done by employing the calcium reactor in a "standard" configuration with tank water and CO2...IMO/E>>
I trust your crew’s advice, as I have lost all faith in the advice I get from my LFS.
<<A shame>>
I have often read the info on your site for hours on end.
<<Me too! [grin]>>
I had mentioned to one of them that I do a lot of reading to learn about this hobby and his recommendation was to stop reading and that most of the info out there is wrong.
<<Ack!  Really?>>
I strongly disagree with his ignorance!
<<bravo>>
Enough said.  Please let me know if you need more info and if I am sending my questions to you in the proper way.
<<In the future, do leave the "entire" previous message intact (don't delete the replies) so we can see who responded to you>>
I only learned how to e-mail about two weeks ago!
<<The age (art?) of technology is upon us...>>
Thank you!
Gary Wallace
<<Happy to assist.  Eric Russell>>

Calcium Reactor Question  - 12/07/06
Good Morning Crew!
<Dave>
I have a couple of questions regarding my Knop S-IV calcium reactor.
The reactor seems to not be circulating the CO2 as well as it should, and therefore not melting the Korallith media.
<For browsers this is the CaCO3 media by Knop>
  How often should you replace the coarse blue filter pads that are at either end of the reactor?
<Don't ever need to be replaced>
Here's my situation, I've had my reactor set up for about 10 months now on a tank that was set up at the same time.  Other than 175 Lbs. of live rock in my 150 gal tank, and a few coral frags, I don't have much of a calcium load.  Animals seem fine, but for the first few months I was able to maintain my calcium and alk with a CO2 rate of 30 BPM, and a drip rate of 3 drops every 2 seconds.
<With an effluent pH of?>
I was using the larger coarse 6 -10mm Korallith reactor media.  My calcium was 390, and my DKH was 9 -10, and my ph was 8.2 - 8.3.  My effluent measured a PH of 6.7 - 6.8,
<Ah, I see>
DKH of 36 and calcium was 500   
<Mmm, okay>
After about 4 months I made an adjustment by accidentally to the needle valve, and had to go through the slow readjustment process, but I wasn't able to maintain the same levels as before.  I started off slowly with the same PH and drip rates as before, but the effluent still wasn't strong enough with a DKH of 16 -18 and a calcium of 450, nor was I able to maintain my calcium and alk levels overall.  I seem to deplete about 1-2 DKH/day and 25 or so of calcium per day, and the effluent levels weren't keeping up.
<Mmm, four months? You very likely just need to replenish the media... or at least shake/consolidate and add to it>
Now, after slowly adjusted the reactor to a drip rate of 5 drops/sec and 120 BPM of CO2 with a PH of 6.6-6.7, and changing the media grain size to medium (3-4mm) am I able to maintain my calcium and alk demand per day, but effluent DKH is still light (about 16-18 DKH), and calcium around 490.  My overall tank levels are 7-8 DKH, ph 8.10 - 8.20, ca 370, and nitrite, nitrate, phosphate = 0, <1, .4.   
<This is fine... I would not change a thing here>
I see lots of bubbles collecting underneath the blue filter pads in the very bottom and upper middle of the reactor, and there's a large bubble that collects under the lid at the top which seems normal, but don't remember ever seeing bubbles underneath the blue coarse filter pads.
<This is most likely due to impurity/ies in your carbon dioxide... Nitrogen, Oxygen... less soluble... look to "higher grade" (more pure) CO2 next re-fill>
It seems to me that the reactor isn't circulating the CO2 as well as it should.
<It won't with air trapped in it>
I've tried rinsing out the filter pads a couple of times, but CO2 still accumulates at the underneath side of the pads.
<Not CO@... this gas is very water soluble...>
  I've also tried turning the reactor upside down and right side up again the get the bubbles to interact with the media some more,
<Good>
but this creates a lot of precipitate to be free floating again, which in turn saturates the blue filter pads in the second chamber (CO2 filter).  I've tried just rocking it back and forth to get the bubbles to enter the pump which creates a lot of swirling bubbles in the pump chamber.  Something is amiss, can you suggest anything?
<The CO2 purity>
Should I try dropping the effluent PH to 6.4?
<No, I would not>
  Should I replace the blue filter pads or soak them in vinegar?
<... you could, but unnecessary... I'd just rinse them off/out vigorously on the occasions you have the unit open>
Should I try the fine reactor media?
<Mmm, I would stick with, use the 10mm nominal diameter... 1082 call-out if memory serves... I've carried several tons of it about...>
I just want to be able to obtain the same effluent levels I had when I first set it up.  I'm also waiting for ph regents so I can calibrate my Pinpoint PH probe just to make sure of my values.  
Thank you,
-David   
<Do ask the gas service if they have other grades of CO2... I do believe this is your principal issue here. Bob Fenner>

Coralline Algae/Alkaline Precipitation/Ca Reactor Tuning - 12/07/06
Hi Eric,
<<Hey Ken!>>
I hope all is well with you.
<<Indeed it is...thank you>>
Things have been going well with the tank, but I have a few questions.
<<Ok>>
The tank is set up 6 weeks now.  The few soft corals and star-polyps look good.
<<Excellent>>
I did buy a clean-up crew about 10 days ago.  I feel like I should put the snails on the payroll.  In the first two days they cleaned all of the greenish algae I had on the rocks.
<<Cool!>>
The tank looks good.  My nitrate is less than 1-ppm and phosphate is zero using LaMotte Colorimeter.
<<Very good>>
The pH is usually 8.10 to 8.20 and ORP has been about 415MV.
<<More good news>>
I also have gotten more and more pink coralline algae on some of the rocks.  My first question has to do with that in the last couple of days I am getting areas of a burgundy color on the rocks.
<<Coralline algae comes in "many" colors>>
It looks to be more on the areas that have some of the pinkish coralline.
<<Conditions in those locations are likely "optimum" for both species...everything competes for space on the reef>>
Also I notice the burgundy color is all of a sudden on a lot of the turbo snails.
<<Very common>>
Is this just another color coralline?
<<Indeed it is>>
I am hoping that it is not like red Cyano or something.
<<Can usually tell the difference>>
I don't see this on most of the rocks and none on sand, powerheads, sand etc.  I tried scraping it off with my fingernail and it does come off somewhat.  It doesn't seem as hard as the pink coralline algae.
<<Differences in structure/composition>>
I'm not sure if this is coralline or not.
<<Likely so>>
I would say that I see this burgundy color mostly on places that had pink to begin with pretty much.  My next question has to do with my AGA Mega Flow.  Their isn't really any algae on my rocks or tank, but I do have some thick greenish layers of it in the overflow box only.  Should I leave it their, or manually remove it, or can I put a couple of my turbo snails in there to eat it.
<<Can remove or leave, whichever you prefer...I would not put turbo snails in the overflow box (will probably get there sooner or later anyway, but...) as they will get in to the overflow pipes and restrict/block flow>>
I thought about snails and overflows but the Durso pipe and the return pipe are sealed unit and nothing could get in there.  What do you think?
<<If you have some kind of "screen" on the Durso then this may be fine>>
By the way, if I manually remove the algae will anything?
<<...?>>
I don't want to spread it around the tank?  Also is it possible that this algae is in its own "container" and it can act like a refugium in a way?
<<Sure...on a very small scale.  If nothing else, it is removing nutrients...but I'll bet close observation will reveal some tiny crustaceans living there as well>>
My last question and most perplexing and bothersome to me has to do with my calcium reactor.  I have an MTC Pro-Cal calcium reactor.  I don't run it all of the time as my tank is only 6 weeks old and there isn't much in the tank to take up the Alk and Ca.  When my alk gets down to 8dKH, I turn on the CO2 and run it at 1 bubble per second and the effluent at .02 ml as per the instructions.  This is their starting point.
<<And as good as any>>
I will shut of the CO2 once the alk hits 10 or 11 dKH.  My Ca usually is in the 410 to 425 ppm range.  The strange thing is that once I run the Ca reactor for a day or so, I see some of the rock (usually more evident where the coralline algae is) start to get a whitish tone to it.  It does not blow off.  Also, and more importantly, when I take a turkey baster, I can blow off what almost looks like ash.
<<Sounds as if you may have some carbonaceous material falling out of solution>>
This has happened all three times I ran it.
<<You may want to consider experimenting with different reactor media>>
I was wondering if it was calcium precipitate, but how could it be?
<<Easy enough...the water can only "hold" so much material.  Maximizing alkalinity (11dKH) and calcium (425ppm) over saturates the water with carbonaceous material.  Try test your alkalinity AND calcium after one of these events...likely BOTH have fallen as a result>>
All of the parameters are in check.  I am not using limewater or any additive and I do 20% water changes weekly with Reef Crystals.
Do you have any ideas?
<<The reactor is probably "too large" for the system (right now anyway) and is producing to much alkaline and calcium reserve than the tank can "use."  I would turn to one of the two-part alkalinity/calcium supplements for now.  Based on your future stocking levels/specimens, you may find you don't need the reactor>>
By the way, I am using CaribSea Geo Thermal aragonite for the media.
<<Mmm, I see...this product is likely soft/more soluble than others...try adjusting the reactor effluent to a pH of about 7.0 the next time you use it and see what results>>
I did buy a Kalk stirrer and plan on using it with my dosing pump and float switch for top off water once I have the time to set it up in a few days.
<<Proceed with caution here...for now anyway>>
I appreciate your help.
Regards,
Ken
<<Always happy to assist.  EricR>>

Re: Coralline Algae/Alkaline Precipitation/Ca Reactor Tuning – 12/07/06
Hey Eric,
<<Ken>>
Thanks for the reply.
<<Welcome>>
With regards to the calcium issue, is it possible that my magnesium could be too low?
<<Testing would tell...but no, this is not the reason your alkalinity rises so fast when the reactor is operating>>
If so, what supplement do you recommend?
<<I prefer the Seachem product...though “small and infrequent” adjustments can be made using simple Epsom Salts>>
By the way, the person at MTC said that I should switch to Instant Ocean instead of Reef Crystals.
<<tomAto-TOMaTO...made/distributed by the same company.  But the Instant Ocean will be fine (is what I use) and will save you a few bucks to boot>>
He said why use salt with all of the extra ingredients in it when you are supplementing the tank anyway with a Ca reactor?  What do you think?
<<The difference in the mixes is of small consequence here...in my opinion>>
Also, I have been doing 20% water change per week.
<<Ah...though water changes are the single best function you can perform, you might consider reducing this to every 3-4 weeks to better give this “new” tank time to stabilize/reach a balance between these changes.  Once the tank has “matured” for a year or so, and if stocking levels warrant, you may find you need to “up” the frequency>>
Do you think this is too much at a time?
<<Too much too often at this stage, yes>>
I can tell you that after the water change, the corals close up for a while and my ORP drops quite a bit.
<<The salt mix is quite “reactive” and irritates the corals/fish...best to let newly mixed salt mature for a week or two while being aerated/moved around with a powerhead>>
All goes back eventually of course.
<<But not without exacting a “toll” in energy used/lost>>
With regards to a two-part supplement, what do you recommend?
<<E.S.V. or C-Balance>>
Do I need to use both parts together to make it work? (Sorry for the dumb question).
<<Yes...do follow manufacturer’s instructions closely>>
Lastly, wouldn't the addition of limewater as top off and no further supplementation or Ca reactor work for me at this point as long as I watch the alk and don't let it go over 11 dKH?
<<You need to monitor both alkalinity AND calcium...these elements are mutually exclusive at the high end of their ranges, which is why you experience the precipitation events>>
I am at 7.5 dKH right now.
<<A “tad” low>>
Why did you note to proceed with caution?
<<You are already having problems with high alkalinity and calcium when running the Ca reactor...utilizing Kalkwasser in conjunction will compound the issue>>
By the way, I evaporate approx 4 or 5 quarts per day right now.
Thanks again.
Regards,
Ken
<<Cheers mate, EricR>>

R2: Coralline Algae/Alkaline Precipitation/Ca Reactor Tuning - 12/08/06
Hey Eric,
<<Ken>>
All noted.
<<Cool>>
You did mention that I had high alkalinity but the testing doesn't bare this out.
<<...?>>
It was high when I first set up the tank, but has been in the 11-12 dKH range ever since.
<<And this is the "high" end of the acceptable range...couple this with calcium levels above 400ppm and you have the "potential" for precipitous events>>
I waited until the alkalinity hit 7-8 dKH before turning on the CO2.  I measured morning and night.  The alk never hit 8dKH but I still got the precipitate.
<<Mmm...pretty sure you stated in a previous query your alkalinity had reached 11dKH and with calcium at 425ppm>>
Something is odd here I think.
<<Hmm, maybe...though likely much to do with the newness/instability of the system>>
Oh yea and Ca was about 415 ppm.
<<Again, on the high end...>>
I didn't even have the CO2 running for 24 hours?
<<I'm still guessing the reactor needs more tuning/backing-off on bubble/effluent rates>>
I am definitely confused.  Good thing that I can rest on the fact that this is a relaxing hobby. :)
<<Ha!  Indeed...>>
Regards,
Ken
<<Be chatting, EricR>>

R3: Coralline Algae/Alkaline Precipitation/Ca Reactor Tuning - 12/08/06
Hi Eric,
<<Hey Ken>>
I did have alkalinity at 11 dKH and calcium at 425 ppm, however the alkalinity was at 8 dKH when I turned on the reactor.
<<Understood>>
I was just confused at the precipitate in the tank.
<<As previously explained...I think (?)>>
I also thought that 1 bubble per second and effluent of .02 ml was not a lot.
<<Is all relative...may very well be/appears to be too much for "your" system>>
I guess I am wrong?
<<Just new...and learning...>>
Anyway, I ordered a new solenoid as the one I have now I cannot adjust under this amount of 1 bubble per second as it doesn't seem to be too fine.
<<Mmm, I see...might have been able to use a simple pinch-clamp on the hose in conjunction with the current solenoid/metering valve>>
Also from what the Ca reactor maker said, it should be running all of the time and not off and on.
<<Bull...how can the "maker" know what your system's needs are/what's best for your tank?  Only by testing can you/anyone determine if the Ca reactor needs to be fed CO2 on a full-time basis.  To help with pH swings, I have my Ca reactor on a timer that turns off the CO2 when the lights come-on on my vegetable refugium (refugium is on a RDP)>>
I will try it at maybe 30 or 40 bubbles per minute and watch the tank and test morning and night for a few days and see what happens.
<<Once you reduce the bubble-rate, adjust the effluent until the effluent pH is about 7.0 with the CaribSea media>>
If I still have issues, should I use something like ESV two-part or Kalkwasser (watching pH of course) until my tank has more of an alkalinity and calcium demand?
<<Try the two-part over the Kalkwasser for now...but honestly...with your current stock list/stocking density, monthly 20% water changes should be quite sufficient for maintaining the tanks earth elements>>
Also the Ca reactor maker recommends aragonite for his reactor, is this a good choice?
<<It is, most all reactor media is a "form" of aragonite.  Do look in to the larger "European style" (10mm nominal) medias as carried by 'Premium Aquatics' and 'Aquarium Specialty' (the latter is owned by a friend of mine).  Scott at Aquarium Specialty also has a Magnesium granulate that can be added to the CA reactor and may help with maintaining this element as well>>
Lastly, I will cut back on my water changes as per the last email.
<<For the best I believe>>
What percent and how many times a month do you recommend?
<<With the tank so new and lightly stocked, I think 25% per month would be just fine>>
Thanks,
Ken
<<Always welcome.  Eric Russell>>

R4: Coralline Algae/Alkaline Precipitation/Ca Reactor Tuning - 12/12/06
Hi Eric,
<<Hello Ken>>
The tank looks good, but I am still trying to figure out the Ca and alk deal.  I haven't added anything to the tank in a week.
<<Good>>
My alk was 9 dKH and Ca was about 385 ppm last night.
<<Both excellent values>>
I changed about 5% water last Friday.
<<...thought we agreed to cut back on this and let the tank find its "balance" *grin*>>
Right now I guess there is no need to do anything.
<<Agreed>>
At what reading do you think I need to take action?
<<As long as alkalinity stays within 8-12 dKH and Ca between 350-450 ppm; and keeping both from being at the high end of their respective range at the same time, then you need do nothing.  If any adjustments do need to be made then make "small" ones>>
I don't want to get involved in that two-part addition additive.
<<Ok>>
I have the Ca reactor and the Kalk stirrer and I would rather go that route when the time comes.
<<Indeed...both are better methodologies.  And you could probably go ahead and use the calcium reactor...with a different (harder) media and "fine tuning" of the reactor effluent>>
By the way, I had checked my Mg and it was somewhere between 1230 and 1260.  So this doesn't appear to be low.
<<Nope>>
You mentioned about a larger media for the Ca reactor.  What would the purpose be for using this over the CaribSea aragonite that I have?
<<Slower dissolution...as it appears now, the calcium reactor is overwhelming your system>
By the way, I did get myself a better Co2 controller for better control over how much is added.  I will hold off on the reactor until for the present.
<<I would try a different media, crank-back the output, and see what happens now>>
With regards to the Kalkwasser stirrer, can I dose some amount with my top off water?
<<You can...if the system will handle it...>>
I have a Liter Meter and it administers is whatever you want to set it at.  It just takes that amount you want to deliver in a 24 hour period and divides it into 150 doses.
<<Understood>>
That looks to be a dose each 9.6 minutes.  So if I dose as per my evaporation rate of a gallon per day, this would mean it would dose .85 of an ounce every 9.6 minutes.  I could also set with a timer and only have it dose for the 12-hour lights-off period.  I would then tell the Liter Meter that it doses 2-gallons a day so that it can dose the 1-gallon in that 12-hour period that is needed.
<<Mmm, better to run 24/7 for better system stability if will be your only means for top-off>>
I could also use a timer and have it dose 1/2-gallon in 12-hours with limewater and then does the other 12-hours with just my ro/di water.  What do you think?
<<Ah, even better to run/dose separately.  I would set the meter to add the fresh top-off water (minus whatever volume of limewater you decide to dose) throughout a 24-hour period, and then set the limewater to be added during "lights out">>
Getting back to my "ash" debris on the rocks.  I had mentioned previously that I noticed this after I ran the Ca reactor.
<<Maybe another indicator that the CaribSea media id being dissolved "too fast">>
However I have not run it in a week and I still noticed it when I blew off the rocks the last few days.
<<Likely the material will not go back in to solution and is resettling...along with detritus in the tank...this is not uncommon/unusual>>
Maybe it is not from the CO2 reactor and maybe not calcium precipitate?
<<Possibly detritus>>
It's hard to describe what it looks like on the rock except debris.  Almost looks like blowing ashes.
<<Does sound like "precipitate"...hmm or maybe...you haven't added a flocculent to your system have you?>>
It is not powdery like what I get when I use the turkey baster and blow out the holes in the rocks.
<<I see>>
Could the rock be breaking down at all?
<<Doubtful>>
The tank itself looks good.  The two tangs and the few soft corals/star-polyps look good.  Phosphate is still zero and nitrate is .15ppm using LaMotte.
<<All good>>
Thanks and regards,
Ken
<<I'll wager everything will "settle in/stabilize" with time and less "fiddling" of the system.  Regards, EricR>>

R5: Coralline Algae/Alkaline Precipitation/Ca Reactor Tuning - 12/14/06
Hey Eric,
<<Hey Ken>>
The 5% water change was not planned.  After having the tank set up for 7 weeks, having the powerheads blow all of the initial stuff around etc, my sump was a mess.  The only way to get it out was with putting a tube on the suction side of a powerhead and send the stuff to a bucket.
<<Ah...ok>>
I ended up going through about 5 gallons of water.  I saw no negative in this at all.
<<Agreed>>
I will check into the other medias for the Ca reactor but before I do, I want to see if I can adjust the CO2 bubble rate with what I have now.
<<A good plan>>
The aragonite I am using now has been used successfully for many people, and maybe I just don't have it set right for my tank presently.
<<This is my primary suspicion...that the reactor is not "tuned" to your system>>
I will wait for the alk and/or Ca to drop and then try the limewater dosing that we discussed (12 hr for ro/di and 12 hr limewater).
<<Ok>>
You mentioned flocculent.  I'm not sure what this is.
<<It is often sold as a "clarifier" to rid the water column of small suspended particles (no place for it in a reef tank in my opinion).  It will "clump" matter together that may resemble the "ash" you mentioned previously>>
Note though that I have not added anything to my tank at all.
<<Noted>>
Thanks and regards,
Ken
<<Cheers mate, Eric Russell>>

R6: Calcium Reactor Issue - 11/09/06
Hey Eric,
<<Hey Ken>>
Well I tested ammonia and nitrite last night (48 hours after the water change).  I got .14 ppm on LaMotte Colorimeter.  I also used Fastest and it looked like the color at the lowest (which could be zero too on this kit).
<<Go with the LaMotte kit's reading>>
Ammonia on LaMotte was zero on Monday night.  Nitrite was 0.792 (after multiplying by 3.3 to convert).  Using Fastest, it was a faint pink color.  It seems to me maybe that the readings are higher than the previous night.
<<Maybe so>>
Was the cycling thrown back maybe?
<<Maybe...marginally>>
Does this mean that the rock won't perform as well, or just that things are delayed?
<<The rock will be fine/unaffected>>
Also to get zero for nitrite, does there have to be perfectly clear in the tube with no tint of color whatsoever?
<<Hmm...whatever the instructions for the particular test kit tells you>>
With regards to calcium and alk.  I'm sure my calcium can't be too high if my alk is, as I don't think chemically that can happen.
<<Um...generally mutually exclusive, agreed...but both can be pushed beyond their limits resulting in a precipitous event as you experienced...best to test>>
If I am going to keep mostly LPS and soft corals, (not sure about SPS at this point), is my calcium reactor a waste?
<<Not at all...LPS have calcareous skeletons and many soft corals utilize calcareous "spicules" for support>>
Am I better off with a Kalkwasser reactor instead?
<<Can be useful...but probably not needed for your system as planned right now>>
Or is a calcium reactor a benefit period to a reef tank.
<<Many times...yes>>
Thanks,
Ken
<<Regards, EricR>>

Equipment list for 500 gallon system   11/26/07
Hello,
<Hey Kirk, JustinN with you this fine evening>
And thank you for answering my question:
<No problems, is what we exist (as a group of like-minded individuals, not as a personal crusade! *grin*) for>
For my Xmas present this year, my wife has given me the OK to get a 450 (96x36x30) custom acrylic gallon tank for our new home.
<Very nice! Quite an undertaking, and quite a woman for letting it happen. *grin*>
The largest tank I have had to this point has been a 125gallon tank. I have been in the saltwater hobby for 8 years, but I must say this is an exciting but seemly overwhelming task.
<Can be daunting>
I know the choice of filtration, pumps, skimmers and crucial to the success of this project.
<Absolutely>
With that said, I would like to know what types of skimmers would you recommend for a tank of this size.  I am going to have a mixture of fish (large angelfish, triggers (pink tail or bluethroat), butterfly (copperband), clowns, and possible a Naso tang) and corals (mostly being LFS and a clam or 2).  I am NOT going to keep SPS corals.
<Am sure you know this, but still feel I must mention that both the angels and the butterfly run a very high possibility of nipping both corals and clams to death.>
Skimmers
------------
The research I have done so far has led me to the following skimmers:
H&S
Bubble King
Deltec
Klaes
I would like to know if a Euroreef or ASM skimmers are a good choice for this large of a tank.  Whatever skimmer I decide on, it needs to be a well design skimmer AND produces a sufficient amount of skimmate.
<I believe any of these would be sufficient. Just to be safe, get a skimmer that is recommended for a tank larger than your overall water volume. That should give you the piece of mind you seek, regardless of manufacturer.>
Filtration/Pumps
-------------------
I am planning on a closed loop system, and for a pump choice it must be quiet and emit low heat.  I was thinking about Dolphin AMP Master pumps, but some other reefers have mentioned larger Bluelines, but I do not know much about them.  Can you offer any suggestions in this area?  How much water flow (i.e., gph/hr) should I plan for??
<Alas, I have no experience with either pump, but going on what I've heard, I hear nothing but glowing praise for the Blueline line of pumps. Sequence pumps also seem to carry a similar reputation. Sorry I'm not of more assistance here.>
Calcium Reactor
------------------
Is this a mandatory piece of equipment with a tank this size? If so, can you suggest some models for me to research.
<I would not consider it mandatory, no, but it will simplify and automate that much more of your maintenance. Korallin, Knop and Tunze all make readily available calcium reactors.>
Thanks for any advice you can give.
Kirk
<Well, wish I could say I had more specific recommendations for you, here, but I think you will do fine. Just read as much reviews of equipment as possible on online forums, talk to local reef clubs, and research before you purchase. Do keep us informed on this wonderful sounding project! -JustinN>

Calcium Reactor Issue - 11/05/06
Hi Eric,
<<Hey Ken>>
I have been looking at my tank the last few days and have noticed the water is hazy and also so was the inside of the glass.  Upon further inspection I notice whitish on live rocks as well.
<<Some earth-element precipitated from solution>>
My thinking is the calcium reactor.
<<Possibly...you also don't "need" to run the reactor at this stage (no abundance of calcifying organisms)>>
I have been running it for a week now at the lowest setting in the instructions.  CO2 at one bubble per second and the effluent at .02ml.  My pH has been about 8.15 to 8.20 using a calibrated probe.
<<Ok>>
I stopped running the CO2 the other day and just let the .02ml pass through.  Do you think this is the reason why I am seeing what I am?
<<From running "without" CO2?  No...it is possible the precipitate is a result of mixing the salt in the tank...and not a real concern right now.  But concerning the calcium reactor...I wouldn't waste my CO2 at this stage were this me...but rather wait until the system is cycles and stocked with calcifying organisms>>
Should I discontinue everything until I get more in the tank?
<<I would discontinue the reactor, yes>>
Should I do a water change even though tank is not finished cycling?
<<Maybe...have you measured calcium/alkalinity?>>
I tested my hardness using Salifert and went through one 1.0 ml titration and had to fill up again. I didn't get a proper reading after the second titration but I would believe that my dKh is somewhere in the 20's.
<<Ah, ok...then perhaps a water change "is" best.  Start with 50% and adjust from there to get these readings back to NSW readings...and disconnect the calcium reactor until it is "needed">>
Will this white stuff on the rocks hurt anything?
<<Not now/with just rock in the system...and should sift down to the substrate eventually (can be "blown off" with a turkey baster/powerhead)>>
Will it go away so that the appearance looks better?
<<As just stated>>
It is not real bad but definitely different than when I put the rock in the tank.
Thanks,
Ken
<<Regards, EricR...off to get things ready for my trip to the Big Island on the morrow!>>

Calcium reactor Issue - 11/05/06
Hi Eric,
<<Hey Ken>>
Which is the big island? Australia?
<<Nope, Australia actually…is a continent...I'm headed to the Big Island of Hawaii>>
Thanks for the replies and hope you have a nice trip.
<<Welcome and thank you.  I’m leaving in the AM to meet up with Bob for some relaxation/dive adventure...and some more tips from the master himself on underwater photography>>
I will do a 50% water change.
<<Cool>>
Will that hurt the cycling?
<<It "may" extend the cycle a bit, but I think it is more important at this point to bring your alkalinity/calcium levels back to NSW levels for the emergent life in/on your live rock and to preclude the possibility of another precipitous event (you've shut down that calcium reactor for now, yes?)>>
By the way, does it matter if the hardness is high now since there is only rock in the tank?
<<It's not "critical" at this stage unless your calcium level is greatly elevated as well...but probably better to go ahead and perform the change>>
Can I/should I wait until after the cycling?
<<Could have waited if you hadn't hooked up the calcium reactor so soon <grin> >>
Thanks and regards,
Ken
<<Cheers mate, Eric Russell>>

R2: Calcium Reactor Issue - 11/07/06
Eric,
<<Ken>>
After I sent you the email I thought of Hawaii.
<<Yes indeed!>>
Have a good time.
<<No worries there...  7am here now...drinking coffee and sitting here with Bob answering queries...hey wait, isn't this supposed to be a vacation?>>
I will do the water change.
<<Very good>>
My water is on the cloudy side now.
<<Will settle out/clear up once your water chemistry is back in balance>>
Probably worse since I re-did the plumbing.
<<I wouldn’t be concerned>>
Any chance I did harm to the rock?
<<Doubtful>>
Thanks again and be safe.
<<Will do Ken.  Cheers, EricR>>
Regards,
Ken

R3: Calcium Reactor Issue - 11/08/06
Hey Eric,
<<Hiya Ken>>
Thanks for the email.
<<Always welcome>>
I'm glad that you arrived safely.
<<Thank you>>
I re-did the plumbing (correctly) this time.
<<Super>>
The tank cannot handle the gph from my pump, so I am using a ball valve on the discharge side of the pump.
<<Common and quite acceptable.  This also gives you the ability to increase flow if/when necessary due to the gradual buildup of organic material inside the plumbing>>
I did a water change that night (Sunday) about 40 gallons.
<<Ah, good>>
So probably equal to a 40% water change give or take.
<<Very good>>
Water was still hazy Monday morning.  I got home last night and the water was clear.
<<Yay!>>
I did some water tests using LaMotte and got: amm = 0, nitrite NO2 = .0957 ppm, and hardness = 15.68 dKH.
<<Still a bit high on the alkalinity, but will probably be fine for now if your calcium level is less than 400ppm>>>
This morning the tank looked real good.
<<Excellent>>
I didn't test for anything yet except for nitrate for the first time.  Using LaMotte I got 7.65 ppm NO3.  I guess I am close the end of the cycling.
<<Mmm, hard to say if you're "close to the end" but things are definitely progressing.  Just keep monitoring water quality and don't get in to too much of a rush to begin stocking the system>>
Do you think that doing the water change I lost some of the bacteria that converts ammonia to nitrite or it doesn't work like that?
<<Opinions will likely vary, but yes, doing partial water changes too early "might" delay/stall a cycle due to sudden dilution of organics/partial die-off of the bacteria colony and subsequent need to "ramp-up" again as the nitrogenous waste builds back up>>
Also since I did the water change, how much should I do at the end of the cycle?
<<I would try to do another 50%>>
Do you think that the rock will "eat" all of the nitrate?
<<Indeed...the bacteria colonizing the rock (all the surfaces in the tank, actually) should bring ammonia/nitrite/nitrate all down to zero (wait a day or so after the water change and retest to be sure)>>
Also I guess I want to get the hardness down even more from the
15.68.
<<Between 8-12 dKH...agreed>>
Thanks again.
<<Quite welcome>>
Be safe.
<<Will do>>
Regards,
Ken
<<Be chatting, EricR>>