Calcium reactor questions

[reef_dude76]

I have been going back and forth trying to decide/figure out should I buy a reactor for my system and how to install it. I have been reading about them here on RC and am confused by a couple of things.

1. The terminology. Is a calcium reactor and a kalk reactor the same thing? In some threads the terms seem to be used interchangably and in others the effluent from the calcium reactor is said to be run through the Kalk reactor to raise the pH of the calcium reactor effluent back up to neutral or higher to prevent pH swings, or low pH levels in the main tank.

2. If the calcium reactor and kalk reactor ARE two different things, then do you need both to balance each other or can you get by with just the calcium reactor?

3. How do you hook up these gadgets. So far I understand the need for CO2, a bubble counter, selenoid, media, but how do you hook it up to the system? Do you need one chamber or two (I assume this depends on the size of the tank and how much calcium you need to replace)? Can you decrease or increase the amount of calcium the reactor puts out? Where do system controller come in to the picture (I have read about many reefers using a pH monitor or system controller to monitor the pH and output form the reactor, how do these controllers help you?)

4. How do you choose one?

I know this is a large number of questions, but I am really confused about this subject, and the more I read the more confused I get.

Help!

 

[jeffbrig]

1. They are two different devices. A kalk reactor mixes makeup water with a powder to create a "kalkwasser" or "limewater" solution. This solution is then added to the tank. A calcium reactor uses CO2 to lower pH enough to dissolve a calcium based media.

2. You aren't required to have both. Many people use only a kalk reactor. Plenty of people use only a calcium reactor. Some people use both to help offset the pH effects. Others use 2-part additives dosed straight from a bottle.

3. A lot of it is choice, and completely up to you. You can increase and decrease the output from a calcium reactor by controlling the amount of effluent it drops into the tank (feed pump rate), or by shutting off the CO2 with a timer. Some people use controllers to monitor tank pH and turn off the CO2 when pH gets too low. I've even heard of a few people who rely on a controller monitoring pH inside the reactor as their primary means of CO2 dosing via a solenoid (not recommended IMO)

4. Keep reading the forums. Get an idea of what reactors work, and what has problematic for people. Find where someone has outlined a setup procedure for the reactor you want, and make sure it's something you understand in and out. Follow it!

In general, when setting up a reactor, pick a starting feed rate for water flowing through the reactor. Then (over a period of time) dial in your CO2 bubble rate so that the pH in the reactor hits your target value to dissolve your chosen media. Monitor calcium and alkalinity in your tank. If it's still dropping, increase the feed rate and start over. If it's going too high, reduce the feed rate, or turn off the CO2 for some period of time each day.

 

[reef_dude76]

In theory, can you accomplish calcium dosing by mixing the kalkwasser yourself and then using an autotop off system to does it into the tank? Rather than using either type of reactor?

 

[jeffbrig]

Yes, the kalk reactor simply automates that process for you.

However, there's one large caveat. You can only add as much kalkwasser as you lose to evaporation. Depending on the Ca/Alk demands of your corals, this may not be enough to maintain proper levels. A Ca reactor has the ability to add enormous amounts of Ca/Alk to your tank, provided you don't push the pH too low in your tank.

 

[scarletknight06]

http://www.reefkeeping.com/issues/2002-05/sh/feature/index.php

read this article on calcium reactors. it explains everything.

 

[reef_dude76]

So dosing kalkwasser is limited by volume, i.e. if you lose 1 gallon of water to evaporation daily then you can only replace 1 gallon with kalkwasser? If your corals need the equivalant of the calcium found in 2 gallons of kalkwasser, then you are only replaceing half the requirement and still 1 gallon short?

Therefore, using a calcium reactor allows for the calcium to be dissolved directly into the water without changing the volume of the system, just the amount of calcium in it?

 

[jeffbrig]

Yep

 

[aquaman222]

I'll throw my .02 in. A calcium reactor can maintain calcium and alk. You will not have much luck raising your cal and alk with just a reactor.

A calcium reactor can and will give newbies a headache. They are often difficult to adjust and can be a PITA.

A kalk reactor will add more than enough cal and alk to a system even if your evaporation rate is small.

Trust me, if your tank needs a kalk reactor you are getting plenty of evaporation due to the heat created by the lights you need to keep the animals that need any reactor at all.

There.

That being said, I use a calcium reactor. I personally like Precision Marine's reactors due to great construction. They are sturdy and well built. Geo also makes one heck of a quality product.

I do not like the fancy reactors with built in pumps and all the crazy gizmos. You just do not need them and they are more expensive to repair and replace parts.

 

[npaden]

<a href=showthread.php?s=&postid=6476860#post6476860 target=_blank>Originally posted</a> by aquaman222
A calcium reactor can and will give newbies a headache. They are often difficult to adjust and can be a PITA.

A kalk reactor will add more than enough cal and alk to a system even if your evaporation rate is small.

I'm not sure I agree. A calcium reactor might be a little harder to setup and the price might give newbies a headache, but actually running a calcium reactor is a breeze compared to trying to mess with 2 part additives and other additives that are eliminated by using a calcium reactor.

I also disagree that a Kalk reactor will be sufficient for a system regardless of evaporation. If you have a tank that is dominated by SPS corals the calcium needs can be tremendous. I've seen 1 coral put on about 10 pounds of growth in a little over a year in my tank. A kalk reactor just can't keep up with that kind of demand if your tank is dominated by fast growing SPS corals.

I run both a calcium reactor and a kalk stirrer on my system.

FWIW, Nathan

 

[EmergencyDpt]

I was reading the article in the link... looks like setting up a meth lab would be easier. I think I'll stick with softies for now. LOL.

 

[reef_dude76]

I was reading the article in the link... looks like setting up a meth lab would be easier. I think I'll stick with softies for now. LOL.

Those are my feelings on the subject too :mixed: After reading that article I see that reactors really "maintain" the calcium level and keep it from yo-yoing up and down. What I found interesting is that apparently for every 1 point you raise the alk the calcium only raises by 20. So you can blow the alk out the roof trying to raise the calcium level. Suppose that you have a tank with an alk of 1 and raise it to 4 with a reactor. That means a Ca increase or "dose of 60" from the reactor. Say you start with a Ca level of 400. This rasies the level to 440. If your corals consume 80 a day, then you are 20 short and the level will start to fall. Thus the reactor doesn't keep the level stable and you have to raise the effluent rate. If coral growth continues to increase and the amount of Ca needed increases can't this create a situation where you still end up needing to dose supplemental Ca even with a reactor?

 

[wrott]

It's really easy to set up and run a Ca reactor--just expensive at first, but in the long run cost is worth it and eventually pays of itself. after adjusting--no maintenance for 6 months--that's pretty nice. My GEO is great---if you have a tank more than 50g I would get a Ca reactor. I drip kalk continuously as well.

 

[reef_dude76]

What is a good model to start with? I have been looking at both precision marine and life reef, any pitfalls with either brand that a beginner might not be aware of?