Upflow vs downflow calcium reactors

[Chin_Lee]

I'm in the process of making a new one but debating the pros and cons comparison between the up and downflow designs. Does anybody have any experiences with this?

[Delphinus]

I was able to switch the direction in two of my reactors which were originally downflow, to experiment with how it would work.

You know what's weird? Both pumps (ie., both reactors) burned out after a few months. One had heat stress so bad it had warped the housing.

I can't explain why it happened. I would have thought downflow was harder on a pump because the media would suffer compaction.

I was using the old style media in both cases.

If I was going with the new coarser media that's more in vogue nowadays, I'd go upflow. Makes sense that it would work better and since it's not the 1-2mm size granules should still leave enough channels open to not overexert a pump.

But if going with the old style media I'd stick with downflow. I'm sticking with downflow until I use up what media I have (I went overboard buying media so I think I have at least a year before it's all used up). After that I'll re-evaluate what it would take to switch over to upflow.

[Chin_Lee]

which pumps were you using

[Delphinus]

Mag2 on the smaller and a Mag3 or Mag5 on the other (think it was a 5 though.. sorry I can't remember already )

[Sebae again]

I would think that the co2 would rise to the top of the canister and create an ''air lock'' so inless you had your output on the top or recirced the co2 your pump might essentially be running '' dry'' and over heating by converting to your upflow design.

[Tom R]

Hi Chin

My first CA reactor used the up flow method. The mixture of water and CO2 caused large bubbles to form under the media. The media would the burp and the system would then release cloudy effluent into my tank. My tank was always muddy looking. It drove me crazy.

I then sold it to some other Reefer and bought an OA Reactor. It's flow is down, no burping however I see a mod is required as it wastes CO2. the mixture of water and CO2 is injected in the top of the camber and the exit for the effluent is also in the top of the chamber. This takes a lot of the CO2 strait out of the system without circulating it through the media. I am going to mod this for better efficiency.
Come on over and you can see for your self.

Tom R

[littlesilvermax]

I use up-flow, but I also have a pcx-30 running my 4 foot tall calcium reactor, well maybe it is taller.

[Pescador]

I recently replaced a K2R down flow with a GEO up flow, they both use the same Eheim pump for recirculation and are fed off the main pump return. I like the large media (it seems to be lasting longer) and the recirc CO2 design keeps any bubbles from collecting in the media chamber.
Probably my favorite feature is the auto-fill on the bubble counter but that's probably not exclusive to up flow.
It does seem easier to over pressure (enough to blow out a uniseal) than the old one but now with two gate valves (1" and 1/2") on the feed it's easy to control.