calcium reactor or kalkwasser reactor

[NeonFish]

Which is better calcium reactor or kalkwasser reactor?

thanks,
Andy

[HighlandReefer]

There are advantages and disadvantages for both of them. ;)

The amount of alk and calcium added by a kalk reactor is limited by the evaporation rate of your tank. A kalk reactor properly tuned will increase your tank pH if it is low.

The calcium reactor can produce more alk and calcium for very high demand SPS tanks, but will reduce the pH of your tank due to the constant flow of CO2 into your tank.

Some hobbyists with high demand tanks, take advantage of both by maxing out the kalk reactor first for pH increase and then supplementing the rest using a calcium reactor.

[HighlandReefer]

Personally I prefer using a still water reservoir for using kalk. This has more control over the saturation of the kalk water than a kalk reactor. A still reservoir will allow contaminates like heavy metals to precipitate out and not be added to your tank where a kalk reactor adds most of the contaminates in kalk. A calcium reactor will add the contaminates to your tank as well.

[lolgranny]

Im glad this was posted as im on the border for both and appreciate your opinion Cliff. Ive been looking into them both and i think i might go the kalk route dosed in by a medical grade dosing unit for topping off the water.

Cliff what are you using to dose kalk with?

[skunkmere]

Personally I prefer using a still water reservoir for using kalk. This has more control over the saturation of the kalk water than a kalk reactor. A still reservoir will allow contaminates like heavy metals to precipitate out and not be added to your tank where a kalk reactor adds most of the contaminates in kalk. A calcium reactor will add the contaminates to your tank as well.

+1 and its really the same or less maintenance of a CR and KR.

[Martin Kuhn]

my recommendation: use none of both, but dose NaHCo3 and CaCl2 in form of liquid solutions (also called Balling's method here in germany ) . In case your tank also consumes Mg, you dose also MgCl2.

let me add another negative thing to
a) "Kalkwasser" / Ca(OH)2 which seems as an outdated option for me: it has shown that there is a risk there are some PO4 depots building up if used for a longer time. time bomb?

b) Besides ph is lowered, ratio of "Ca" vs "Alkalinity" can't be really controlled.

Balling's method has none of this disadvantages and is the clear favorite in my opinion.

regards
Martin

[bertoni]

I don't know of any risks associated with kalk. It's a fine option, IMO. The control of alkalinity vs calcium is quite easy. Just dose one or the other. :) It's true that kalk alone isn't useful for that purpose, but baking soda is inexpensive.

[HighlandReefer]

Im glad this was posted as im on the border for both and appreciate your opinion Cliff. Ive been looking into them both and i think i might go the kalk route dosed in by a medical grade dosing unit for topping off the water.

Cliff what are you using to dose kalk with?

I use the BRS calcium Hydroxide (kalk) since it is pharmacuetical grade. I mix it in a 55 gallon drum and use a Reef-Filler adjustable dosing pump, like Randy does. ;)

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"let me add another negative thing to
a) "Kalkwasser" / Ca(OH)2 which seems as an outdated option for me: it has shown that there is a risk there are some PO4 depots building up if used for a longer time. time bomb?"

Kalk does contain phosphate and a lot will depend on the grade. The amount in pharmacuetical grade is less than 0.5%. Keep in mind that the phosphate in kalk water is likely to precipitate out with the the contaminates since the phosphate has a high affinity with the calcium carbonate precipitatants. Even if it doesn't precipitate out the amount of phosphate added by kalk water is nothing compared to the amount of phosphate added by fish foods. Some phosphate may be present in your sodium carbonate and calcium chloride supplements as well.

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Using two-part is a fine way to supplement alk and calcium, but is more expensive and when you have large tanks the cost can be quite high compared to kalk water, kalk reactor and especially a calcium reactor which is the cheapest once you buy the equipement. :)

Randy compares all the methods used to supplement alk and calcium and their costs in this article for those interested:

How to Select a Calcium and Alkalinity Supplementation Scheme
http://www.advancedaquarist.com/issues/feb2003/chem.htm

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Randy discusses phosphate in kalk water in this article:

What Your Grandmother Never Told You About Lime
http://reefkeeping.com/issues/2005-01/rhf/index.htm

From it:

"What Else Does Limewater Do In An Aquarium? Reduce Phosphate

Many reefkeepers accept the concept that adding limewater reduces phosphate levels. This may be true, but the mechanism remains to be demonstrated. Craig Bingman has done a variety of experiments related to this hypothesis, and has published them in the old Aquarium Frontiers. While many aquarists may not care what the mechanism is, knowing it would help to understand the limits of this method, and how it might best be employed.

Habib Sekha (Salifert) has pointed out that limewater additions may lead to substantial precipitation of calcium carbonate in reef aquaria. This idea makes perfect sense. After all, it is certainly not the case that large numbers of reef aquaria will exactly balance calcification needs by replacing all evaporated water with saturated limewater. And yet, many find that calcium and alkalinity levels are stable over long time periods with just that scenario. One way that can be true is if the excess calcium and alkalinity that such additions typically dump into the aquarium are subsequently removed by precipitation of calcium carbonate (such as on heaters, pumps, sand, live rock, etc.).

It is this ongoing precipitation of calcium carbonate, then, that may reduce the phosphate levels: phosphate binds to these growing surfaces, and becomes part of the solid precipitate. The absorption of phosphate from seawater onto aragonite is pH dependent, with the binding maximized at around pH 8.4 and with less binding at lower and higher pH values. If the calcium carbonate crystal is static (not growing), then this process is reversible, and the aragonite can act as a reservoir for phosphate. This reservoir can inhibit the complete removal of excess phosphate from a reef aquarium that has experienced very high phosphate levels, and may permit algae to continue to thrive despite having cut off all external phosphate sources. In such extreme cases, removal of the substrate may even be required.

If the calcium carbonate deposits are growing, then phosphate may get buried in the growing crystal, which can act as a sink for phosphate, at least until that CaCO3 somehow dissolves. Additionally, if these crystals are in the water column (e.g., if they form at the local area where limewater hits the tank water), then they may become coated with organics and be skimmed out of the aquarium.

An alternative mechanism for phosphate reduction via limewater may simply be the precipitation of calcium phosphate, Ca3(PO4)2. The water in many reef aquaria will be supersaturated with this material, as the equilibrium saturation concentration in normal seawater is only 0.002 ppm phosphate. The supersaturation of calcium phosphate will be even higher in the high pH/high calcium fluid present where limewater enters reef aquaria. The locally high pH converts much of the HPO4-- to PO4---, and it is the concentration of PO4--- that ultimately determines supersaturation. That high supersaturation may tip the balance to precipitation of calcium phosphate, just as too much limewater all at once can tip the balance to precipitation of calcium carbonate. As with CaCO3, the precipitation of Ca3(PO4)2 in seawater may be limited more by kinetic factors than by equilibrium factors, so it is impossible to say how much might precipitate under reef tank conditions (without, of course, somehow determining it experimentally).

As with the precipitation of CaCO3 containing some phosphate, if these calcium phosphate crystals are in the water column (e.g., if they form at the local area where limewater hits the tank water), then they may become coated with organics and be skimmed out of the aquarium."

[lolgranny]

Thanks for the suggestion Cliff. Have you had any issues with it? I was looking at this one which one of my buddies use. http://www.innovativeaquatics.com/

How do you set the amount to be dosed on the unit you linked?

Thanks again

[zigzag1]

there are advantages and disadvantages for both of them. ;)

the amount of alk and calcium added by a kalk reactor is limited by the evaporation rate of your tank. A kalk reactor properly tuned will increase your tank ph if it is low.

The calcium reactor can produce more alk and calcium for very high demand sps tanks, but will reduce the ph of your tank due to the constant flow of co2 into your tank.

Some hobbyists with high demand tanks, take advantage of both by maxing out the kalk reactor first for ph increase and then supplementing the rest using a calcium reactor.

+1

[NeonFish]

Looks like I have a little research to do. thanks for all you help.

[HighlandReefer]

Thanks for the suggestion Cliff. Have you had any issues with it? I was looking at this one which one of my buddies use. http://www.innovativeaquatics.com/

How do you set the amount to be dosed on the unit you linked?

Thanks again

With the Reef-Filler adjustable dosing pumps you can dial the amount you want dosed. Once you get the dosing rate correct, you pretty much forget about it. I have no needed to adjust mine in years. There is no need for any kind of timer using this type of pump and it is re-buildable. ;)


http://www.championlighting.com/pics/doserpics/reeffiller1001.jpg

[vbsaltydog]

I use a Kalk reactor with Mrs. Wages Pickling lime in line with my ATO. It does a great job of adding ALK and Ca but it raises my pH pretty high due to the pH 11 of saturated Kalk. What methods are being employed to allow Kalk (reactor) dosing without raising the pH out of spec?

I was thinking of having a two-stage ATO. Using my Apex, the ATO always adds RO as top off during the photosynthetic daylight hours and at night, when the pH is at its lowest, check the pH when the ATO triggers and if the pH is below 8.15, top off from the reactor, otherwise top off from the RO.

Thoughts?

[HighlandReefer]

Your pH range should fall between 7.8 - 8.5. As long as it remains between these levels you are fine.

Some hobbyists dose kalk water (use there kalk reactor) at night when the pH is the lowest. You want to limit the flow through your kalk reactor to prevent spiking the pH level above 8.5.

[rogergolf66]

my recommendation: use none of both, but dose NaHCo3 and CaCl2 in form of liquid solutions (also called Balling's method here in germany ) . In case your tank also consumes Mg, you dose also MgCl2.

let me add another negative thing to
a) "Kalkwasser" / Ca(OH)2 which seems as an outdated option for me: it has shown that there is a risk there are some PO4 depots building up if used for a longer time. time bomb?

b) Besides ph is lowered, ratio of "Ca" vs "Alkalinity" can't be really controlled.

Balling's method has none of this disadvantages and is the clear favorite in my opinion.

regards
Martin

Why couldn't I find anything on the Balling's method when I did a search on RC?

Roger

[TampaSnooker]

Why couldn't I find anything on the Balling's method when I did a search on RC?

Roger

I think it's more commonly referred to as "randy's recipe" on RC. I can never find the link to the article in reefkeeping online mag, but the title is "An Improved Do-it-Yourself Two-Part Calcium and Alkalinity Supplement System". It has great detail.

[NeonFish]

found a reference here: http://www.thereef.info/balling.htm

[TampaSnooker]

and Cliff posted the link I was looking for in another thread:
http://reefkeeping.com/issues/2006-02/rhf/index.php

[bertoni]

Balling's method was developed quite a while ago. There are some variations, but the major difference between the DIY 2-part and the Balling method is the dosing of trace elements, and maybe the automation of magnesium dosing, depending on all the variations that you consider.