Nilsen Reactor vs. Calcium Reactor

[jgagel]

I was wondering if it is possible to only use a Nilsen Reactor on a tank and keep calcium and alkalinity levels high and stable, and keep a steady pH level. It seems like most everyone use a Calcium Reactor and may supplement a Nilsen or Kalk Reactor. The Nilsen reactor is cheaper so why don't people use a Nilsen Reactor and forget the pricey Calcium Reactor? I would greatly appreciate the help because I am on a budget, I am looking for the most efficient stable way to increase calcium, alkalinity, and keep a steady pH.

 

[Anonymous]

the nilsen reactor is limited by the amount of evaporation your system is subject to. You can only replace as much as evaporates.

However, if you have a fairly new set up, your calcium needs are probably not that great and the Nilsen should keep up fine. Also, you can dose kalk manually to add to the Nilsens contribution.

I'm currently using a DIY Nilsen on a new reef, and probably will add the CA reactor in 6 months or so.

 

[danmhippo]

It depends on your evaporation rate. Nielson reactor mixes kalk with RO water, whereas Calcium reactor recycles tank water. If you have a big tank with daily evaporation rate of over 1% of total volume (eg. a gallon or 2 a day for a 150Gallon tank), you may be able to maintain alk and ca up with just nielson reactor.

However, if your tank is relatively small and only evaporates 1/4 to 1/2 gallon a day, you may not be able to keep calcium demanding corals and clams, because you can only drip in so much or freshwater a day.

Another reason some uses strictly Calcium reactor is the ease of maintenance. Nielson reactor typically only holds a cup to 2 cups of kalk in each refill. Too much kalk added, the stirrer (or the pump) may not spin correctly. That means each refill only lasts you anywhere from 3 weeks to 3 months, depending on the need of your tank.

Calcium reactor on the otherhand, goes a lot longer. Pretty much once you set it up, you can forget about it for 6 months plus, as long as you have enough CO2.

I am currently only relying on nielson reactor and water changes to maintain my alk and ca level.

 

[Mac1]

Ditto what Dan and Dan said... Kalk is cheaper and easier, but... Can only do so much. It's easy enough to increase your evap rate (add a fan?) if you're not able to keep up w/ the demand in your tank, however some people feel obligated to get pricey, nifty, toys for their tanks. Admittedly, a Ca Rxr I think does a better job, it replaces the entire corals skeleton), although that includes the good and the bad parts as well. Kalk Rxr's simply replace the calcium and alkalinity components in the water, nothing more, nothing less. I have firends w/ heavily loaded tanks and Ca Rxr's, who are actually supplementing their tank w/ Kalk because they can't keep the Ca high enough w/ a Rxr alone, and the CO2 is causing problems for them in their reef (depressed pH).

Unless you have a fully-stocked SPS tank, I'm willing to bet that a Kalk Rxr will more than take care of your needs for some time to come.

- Mac