Ca/Alk - Is this normal?

[Cuttlefish]

Yesterday I must have dosed a 2 part B Ionic 4 times throughout the day. Each time I used the recommended dose for my tank, it seemed depleted within 2 hours. I have alot of Coralline algae now and like two medium sized SPS frags. What else could be causing this rapid calicium depletion? Ill also be going through test regeants very fast. 4 tests of both Alk and Ca adds up.

I can now see why people recommend spending the $ on a calcium reactor cuz this is gonna get ridiculous. I thought at worst Id have to buy another 2 part once or twice a month. But at this rate I'll be going through 2 per week lol. I suppose kalkwasser is a better option. Or maybe Ill keep dosing for a while til I can afford a reactor. Ill just buy the XL B Ionic containers. Cheaper in bulk right?

On the bright side, the growth is enjoyable to watch. I wonder if half of this Ca usage is the fact that Ive let Coralline algae growth unrestricted all over the glass. I imagine that alone is requiring a good amount of Ca.

SO is this normal?

Are there any advantages to using a 2 part over Kalk?

[fihsboy]

I actually enjoy Oceans Blend much better then the other brands. I does 20ml every morning, did the math today. Thats 90 bucks a year.....but I would have to use a calcium reactor for about 11 years to break even......now thats an investment. How big is your tank? I would say your getting faulty readings from your tests. PLUS, it takes a good 4-6 hours for your levels to settle down so you can read them accuratly. All that calcium will eventaully precipatate and it will start to clog your pumps up. Nothing a good vinegar bath wont take care of.........but its a pain. After you run out of the B-Ionic....try Oceans Blend. You wont be sorry. And you can get the 10 gallon set for 60ish bucks.....which for me would make it around 55-60 bucks a year....

[tdwyatt]

Originally Posted by fihsboy

I actually enjoy Oceans Blend much better then the other brands. I does 20ml every morning, did the math today. Thats 90 bucks a year.....but I would have to use a calcium reactor for about 11 years to break even......now thats an investment. How big is your tank? I would say your getting faulty readings from your tests. PLUS, it takes a good 4-6 hours for your levels to settle down so you can read them accuratly. All that calcium will eventaully precipatate and it will start to clog your pumps up. Nothing a good vinegar bath wont take care of.........but its a pain. After you run out of the B-Ionic....try Oceans Blend. You wont be sorry. And you can get the 10 gallon set for 60ish bucks.....which for me would make it around 55-60 bucks a year....

This is just another 2-part calcium and alkalinity additive, with the disadvantage of adding Mg++ along with the calcium and alk PLUS a truckload of trace elements. These extras are added in proportion to your calcium and alk, so that you end up not being in control of these additives if you dose in relation to your calcium and/or alkalinity. It is basically Bionic (which is just about as concentrated as the solubility of CaCl2 and NaHCO3 in equimolar mounts will allow) plus Mg++ and trace elements, not good.

You're better off using a plain 2 part, or better still, avoid the issue of all two-part additives with the unused sodium and chloride (that skew your conservative proportionality of your ASW) and use kalkwasser as your topoff. Pickling lime is about $2 USD a pound, and you can get it at Wallyworld.

AND THERE IS NO ISSUE WITH THE ADDED SODIUM AND CHLORIDE SKEWING UP YOUR SALINITY AND ASW composition...

there site is not a lot of info re: product comp, but it is:
http://www.oceansblend.com/2_part.html

[fihsboy]

Ive had outstanding growth rates with it, Should I try pickling lime? just for kicks and giggles. I have an ATO, I would just have to figure out my dosage rate. And do I mix it constantly or let the white goo settle to the bottom of my top off water container. It sure would be cheaper.

[tdwyatt]

Originally Posted by fihsboy

Ive had outstanding growth rates with it, Should I try pickling lime? just for kicks and giggles. I have an ATO, I would just have to figure out my dosage rate. And do I mix it constantly or let the white goo settle to the bottom of my top off water container. It sure would be cheaper.

One of the cheapo ghetto methods involves putting the pickling lime in the ATO reservoir, putting the ATO pump on a brick, and letting the suspension settle after a good stir with a wooden spoon. This will be fine until you need to refill the reservoir with water, at which time, just pour in more water and stir it up again, adding another tablespoonful (three teaspoonful) of pickling lime per 6 gallons (the size of a salt bucket is about this). As the Ca(OH)2 settles, the water in the bucket re-saturates, and it is ready to go again. Keeping the powerhead on the brick allows the pump to run without being in the precipitate, and the pump will last much longer. Although the kalkwasser will react at the surface to make CaCO3, this is a relatively slow process and is insignificant in the big picture (unless you continually stir the bucket or bubble your breath or CO2 through it, even then, the resulting CaCO3 is utilized by the tank). I have suggested floating a piece of styrofoam on the surface cut to fit the bucket, leaving a cutout for the power cord for the PH and the ATO hose, but I feel this is probably not nuecessary.

A more technological, automated method is to use a kalkreactor (Nielssen reactor) between the ATO reservoir and the sump, so that the water pumped into the reactor displaces an equal volume of kalkwasser that is routed to the sump, and the water pumped into the reactor is mixed with the excess Ca(OH)2 slurry in the bottom of the reactor to make kalkwasser. There are many DIY kalkwasser reactor plans on the 'Net, as well as many manufactured units through dry goods providers.

I have used both method with great success, and the ghetto method maintains Calcium and alk at 400+ PPM (CA++) and 9-10 dKH (alkalinity) levels until hermatypic growth gets too heavy. It works well with prop systems as long as total system volume is large (big sump ~= to tank size) and the frags are not too big (< 6cm specimens).


I trust this is clear, HTH.

[fihsboy]

Kalk reactor sounds a LOT cleaner. Ill be the guinea pig on this one. Anyone else use kalkwasser? Whats the downfall? Why doesnt everyone use it? ive been dosing two part for over two years, and im getting tired of doing it every morning!

[tdwyatt]

If you use a float switch to control your ATO, I would suggest making sure that you have some safety Backup in at least a Maximum depth switch for thge sump. This is just in case the switch that calls for the pump fails in the "on" position. Flooding even a 180 USG tank with 5 gallons of kalkwasser could be a real problem, and I don't mean from a drop in salinity; God forbid that the tank volume be less.

Having a lot of tank and sump volume is cheap insurance, but i'd still have a max depth switch for the ATO in the sump.


HTH

[fihsboy]

Just ordered new switches, so I will have a backup switch. Ill give it a shot.

[bb0029]

I still don't understand how the Ca and Alk work with or against each other.

[tdwyatt]

Originally Posted by bb0029

I still don't understand how the Ca and Alk work with or against each other.

If your Calcium is anything above 375 PPM, your corals will be fine, so long as there is a balance of an appropriate amount of Dissolved Inorganic Carbon (DIC = all carbonate species in the water column = alkalinity and pCO2) and you keep your supplementation up. For closed systems, a Ca of 400 to 425 PPM is probably best, along with a matching alkalinity of 10 to 12 dKH. Your calcium at 500 PPM will prevent you from getting much more alkalinity into the water column without having it begin to abiotically precipitate out on heaters, etc, or causing a snow storm. Both of these events will cause your calcium to drop (think about it, where does the calcium to make CaCO3 come from when you add extra alkalinity and it causes precipitation?)

When alkalinity gets much higher, it begins to precipitate Mg++ out as MgCO3 as well... hmmmm... Remember that when you use MgSO4 (Epsom salts), you start skewing your conservative proportionality... does this sound like it might be a common problem?


If we consider the conditions of salinity, temperature, pressure, pCO2, the presence of other ions as steady and constant, and there are no other changes in the factors that affect the supersaturation quotient (i.e., temps don't drop, salinity does not change, magnesium does not shift, etc...), then any changes in the concentration of calcium or alkalinity will affect the supersaturation quotient in such a manner, because variable conditions are in the numerator of the quotient formula, and are factors of each other (they are multiplied together and the product is multiplied by a constant in our circumstances, then divided by a constant value), so the changes in the concentrations of the variables (the water column values of Ca++ and alkalinity) will stay in a multiplicative proportion to each other if the water column is at its maximum supersaturation state, See this post starting at post 25 or so for the actual mathematics . If the water column is not saturated with respect to one or the other ions, then even if the numbers cause saturation states to be exceeded, then equal numbers of both ions of a salt (here, C++ AND HCO3- as CO3--) will STILL be precipitated, but any available sources of the ion not at saturation will be able to go back into the water column as an ion (never thought I'd be talking p-chem in an aquarium forum... )

W = [Ca++][CO3--]/Ksp

If everything else in the formula does not change, and the water column is at max supersaturation with respect to calcium and bicarbonate, then any addition of either of these substances results in precipitation such that the precipitate must have equal parts of both components (ions) to precipitate, and any increase in either one of the two factors MUST DECREASE THE OTHER IN EQUIMOLAR AMOUNTS IN ORDER TO RETURN TO MAX SUPERSATURATION. This means that if you add one part of a two part supplement that pushes the supersaturation quotient into precipitation range (because it increases the value of the ion added in the formula) it will reduce both parts of the supplement down by an equal number of molecules (the reaction is a one to one ratio) until the supersaturation quotient (equilibrium) is reestablished for these new conditions.


I'll present an example using numbers NOT representing a set of actual conditions, rather a set of numbers to represent the math (and I'll bend the actual mechanics a bit to make it clearer to comprehend the kinetics). If the supersaturation quotient were such that the product (the concentration of the calcium ions multiplied times the concentration of the alkalinity) of the two numbers was 4000 for those conditions, (say 400 for calcium and 10 for alkalinity, remember, these are just to show the math), then if we increase the calcium to 500, our alkalinity will drop via precipitation of CaCO3 to 8 in order to keep the product constant at the max supersaturation quotient (  (500 x 8 = 4000 ) If we push the Ca++ to 600 (here, this is unit-less), our alkalinity will drop to 6.67 (6.67 x 600 = ~4000 )


Suppose we pull out our trusty Salifert test kits and discover that despite our best efforts that our alkalinity is low and calcium is sky high, say oh, idunno, maybe 600PPM ) ... All we would need to add is alkalinity (and there are calculators on the ‘Net to determine how much we need to add that will precipitate some of the calcium) and increase our bicarbonate level to our desired supersaturation state. In our example, our product of the two factors is 4000, and we desire to raise our alkalinity to 10, so it would initially seem that we should be able to add 3.33 alkalinity units to increase our alkalinity to 10 (and consequently decrease our Ca to 400). As this will precipitate equimolar amounts of calcium as the bicarbonate pushes the supersaturation quotient into precipitation, we will see the calcium fall, but what happens to the alkalinity? This is what many aquarists think when they say "...I added buffer (sodium bicarbonate), but the alkalinity value didn't budge, however, my calcium IS coming down..." Although this may not be exact, we would most likely need to DOUBLE the amount of bicarbonate we add (6.67 units) to reach our goal of 10 Remember, we are losing alkalinity as it combines with the calcium ions to form calcium carbonate as the calcium precipitates. We not only want to precipitate out the Ca++ initially, but we will then need to increase our alkalinity value to a point where balanced additions will maintain the Calcium supersaturation quotient at or near the max supersaturation for conditions in our tank.


I took a LOT of liberties describing how this works, but this is a simple version that relays the concept without getting into the kinetics of the chemistry.


Just because we use a calcium reactor, it doesn't mean we avoid problems with this topic. Suppose we have a stumped aquarist that posts…

Originally Posted by Mike

...and I have a CA reactor running (which a year later, I STILL doubt I've got dialed in right), and I'm dosing Ca++ as well. And all either do, is raise my Alkalinity. (which makes NO sense).

It makes perfect sense. The use of the Ca reactor with CO2 has much to do with this, as the excess CO2 under the right circumstances will actually be converted to alkalinity given enough time and a proton acceptor in the water column. When you make changes to the reactor environment, you need to wait a few days before you will see the final results of the changes on the reactor environment and the tank. When this aquarist is adding calcium, it is raising total calcium to a level that exceeds he supersaturation quotient, and it precipitates calcium Carbonate, but we continue to add CO2, which continues to dissolve aragonite in what might seem like insignificant amounts of Ca++, but huge amounts of alkalinity. Remember that Ca++ reactors dissolve aragonite at equimolar amounts, which will show up as 20 PPM of Ca++ for every 50 PPM alkalinity* (1 mEq = 2.8dKH), so continued of the reactor while boosting hermtypics should always appear to have large increases in alkalinity (including adding either alkalinity or calcium), which as they exceed the quotient again, will drop Ca++ even lower: a viscous circle.

I hope this make the issue a bit easier to understand.



*See http://www.reefkeeping.com/issues/2004-12/rhf/index.php for effect of Mg++ and Sr++ on this.

[three90s&125sump]

It definatly confirms what I have been arguing for some time. I get told I'm wrong about that quite often. Thanks tom!

[Cuttlefish]

Thats quite an in depth explaination but over my head guys. I know Ca, Alk and Mg need to be balanced as their levels all inhinge upon each other. The proper balance provides bioavailiblity and things grow. Alk provides the means for the Ca to be absorbed and Mg fits in there somewhere as well. Thats about all I really need to know at this point cuz even though I LOVE biology, the chemistry part of it I dont care to completely wrap my head around.

But no matter how much 2 part dosing im doing and how fast it ges depleted, the tank is doing great. I could not be happier with the state of things. The only problem is the cost and frequency of the dosing and testing. Ill gladly deal with it though as long as these ideal conditions persist, but if Kalk is just as effective as a 2 part, but much cheaper and practical, ill go with that. One day I will get a Ca reactor though, its just hard right now to justify a $500-$600 purcahse.

[three90s&125sump]

Its funny... I'm way into the chemistry aspect but really behind on the biology part. I get the nitrogen cycle pretty well but I fall really short when it comes to the needs of the animals. I know some but not nearly enough.

But you do need to know more about the chemstry because dosing 2 part for long periods of times can seriously compromise water quality.

[tdwyatt]

You don't need to know all the gory details, so long as you understand that they occur and can affect the big picture (or don't affect the big picture depending on circumstances).


HTH

[bb0029]

Originally Posted by tdwyatt

You don't need to know all the gory details, so long as you understand that they occur and can affect the big picture (or don't affect the big picture depending on circumstances).


HTH

Ok thanks, that was a lot of stuff to take in but I think I have a better understanding of how they work with or against each other. I have always read where they feed off one another but never really understood why.