Advise on Equipment for Current & Future Tank (Calcium Reactor or Kalk Reactor)

[bassettmd]

Hello,

My question pertains to maintaining my calcium and alkalinity levels in my current 65 gallon tank and my future 200 gallon total water volume set up. My current tank consists of many soft corals and a large variety of LPS as well as many large clams (gigas 16", squammy 8", maxima). Currently I only need to dose once a week to maintain my levels within parameters while using kalk in my top off water; The predominant reason is that I leave my tank every week because it is located at my parents house while I live and go to school in boulder (about an hour away). My parents know nothing of reef tanks except for how to feed the fish.... therefore I like to automate everything as much as possible for my benefit and theirs as well. I would like to add some more stability to my calc and alk parameters.

However, I am currently growing many SPS frags on a small frag shelf in preparation for a future 120 - 150 gallon tank. My for my future tank is to have two islands, one LPS and softie dominated and the other SPS dominated.

My dilemma arises with the fact that I would like to purchase oversize equipment that would accomodate my current tank as well as my future tank. However, I have heard many different opinoins on the matter and would like to hear a few more. Should I purchase either a kalk reactor or calcium reactor in order to provide more stability in my parameters and meet the ever growing need of my clams and sps? should I buy both (an expensive option... would it be worth it?)? Whos brand would people reccomend? Personal experience? How long have you owned it?

THANKS IN ADVANCE!

[skydancer]

For starters here is a good article on the different methods of maintaining Calcium and alkalinity with all their pros and cons.

http://www.peteducation.com/article....articleid=2999

[sjm817]

I read through the article (not all of it), and saw a couple of problems:

Over time, the use of kalkwasser lowers the alkalinity in the tank. As a result, buffer also has to be added from time to time when kalkwasser is used.

The biggest drawback is that kalkwasser needs to be fresh. It should not sit in its mixed form for very long or else it interacts with atmospheric carbon dioxide and converts into insoluble calcium carbonate. As a result, kalkwasser should be mixed up daily before it is added to the tank.

Cant say I agree with those statements.
Here are some other articles to look through written by Dr Randy-Holmes Farley:

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

A Simplified Guide to the Relationship Between Calcium, Alkalinity, Magnesium and pH
http://reefkeeping.com/issues/2006-06/rhf/index.php

When Do Calcium and Alkalinity Demand Not Exactly Balance?
http://reefkeeping.com/issues/2004-12/rhf/index.htm

An Improved Do-it-Yourself Two-Part Calcium and Alkalinity Supplement System
http://reefkeeping.com/issues/2006-02/rhf/index.php

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

The Self Purification of Limewater (Kalkwasser)
http://www.advancedaquarist.com/issues/may2003/chem.htm

The Degradation of Limewater (Kalkwasser) in Air
http://www.reefkeeping.com/issues/20...ture/index.php

[bassettmd]

Anyone have any experience maintaining a large tank with either kalkwasser or a calcium reactor? Which brand name products would you guys reccommend?

[skydancer]

sjm,

I agree with you about the second statement, it is debatable. It is probably a good idea to monitor how much the kalkwasser is saturated by measuring the conductivity or PH inside the reactor / container / stirrer.

But the first statement above is absolutely true. If you only dose kalkwasser and NOTHING else your alkalinity WILL drop. The PH will stay high because Kalk will keep it hi ionically, but there is no bi-carbonate molecules in calcium hydroxide and your corals skeleton will not grow. You'll need to have buffer, baking soda or something added over time.

[skydancer]

Originally posted by bassettmd
Anyone have any experience maintaining a large tank with either kalkwasser or a calcium reactor? Which brand name products would you guys reccommend?

The ideal system for a large tank, or probably for any tank for that matter is a combination system of:

calcium reactor + kalkwasser reactor/stirrer/container

or

2-part dosing + kalkwasser reactor/stirrer/container.

My experience has been with the 2-part dosing but lately my system's Cal/Alk requirements have increased significantly and started dosing kalk for 2 reasons (calcium supplementation and keeping the PH more stable 24/7)

[sjm817]

Originally posted by skydancer
sjm,

I agree with you about the second statement, it is debatable. It is probably a good idea to monitor how much the kalkwasser is saturated by measuring the conductivity or PH inside the reactor / container / stirrer.

But the first statement above is absolutely true. If you only dose kalkwasser and NOTHING else your alkalinity WILL drop. The PH will stay high because Kalk will keep it hi ionically, but there is no bi-carbonate molecules in calcium hydroxide and your corals skeleton will not grow. You'll need to have buffer, baking soda or something added over time.

This is covered in the articles linked above. Limewater adds ca and alk in balanced proportions.

The calcium ions in the solution obviously supply calcium to the aquarium, and the hydroxide ions supply alkalinity. Hydroxide itself provides alkalinity (both by definition and as measured with an alkalinity test), but corals consume alkalinity as bicarbonate, not hydroxide. Fortunately, when limewater is used in a reef aquarium, it quickly combines with atmospheric and dissolved carbon dioxide and bicarbonate to form bicarbonate and carbonate:

4. OH- + CO2 à HCO3-

5. OH- + HCO3- à CO3-- + H2O

[skydancer]

Yes sjm, you're right... small detail that I'd overlooked...

It now makes more sense why you'd want to combine kalk dosing with a calcium reactor...
...that would be how the excess CO2 coming out of the ca reactor is being eliminated...

[sjm817]

I got to tell you, RHF and the Reef Chemistry forum is just incredible. There is just a wealth of information there, some incredibly knowledgeable people. I dont how I could run my tank without them. I dont know anything about chemistry. It seems like you do.