Upflow vs downflow calcium reactors

[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.