Ok. So I swapped the ceramic rings in the reactor out for the original bioballs for the reactor. While I was at it, I switched the tubing out, so that the reactor now is mounted after the filter, rather than before. Switching back to the bioballs made a massive difference. The flow of the filter was radically improved - also even though the reactor was mounted after the filter, rather than before. I would guess that the reactor, after switching back to the bioballs, reduces the flowrate of 10-20%, which to me is acceptable. The absorbtion rate of the reactor is all of a sudden massively improved also. It seems to me that this can be attributed to either of two factors. Sufficient flow (around 1000 l/hour) and/or higher pressure in the reactor, due to it being mounted after the filter, rather than before (at 1200 l/hour the filter actually creates a siginificant underpressure on the intake side). At a flowrate of 1000 l/h I had trouble, that the CO2 from outlet of the reactor was sucked directly into the outflow, rather than stay in the reactor. By standard the CO2 is bubbled out by a tube near the outlet of the reactor. Removing the tube, so that the CO2 bubbles out in the top of the reactor instead, completely remedied this issue.
I originaly swapped out the bioballs due to people on forums advocating that Eheim Mix (rough mechanical filter material) or ceramic rings would improve absorbtion rates. I've tried both and my conclusions are these. At flowrates of 1000 l/h Eheim Mix is inefficient, as the waterjet of the filter, simply sprays right through the material in the reactor. Ceramic media on the contrary reduces and restricts the waterflow so much, that the reactor (and the filter) becomes inefficient. It also has the negative effect of creating smaller co2 bubbles that reach the output side of the reactor, either escaping in to the filter or out in the aquarium itself - depending on whether the reactor is mounted before or after the filter.
To sum it up - here's my advice on the Aqua Medic 1000 reactor, based on my own observations:
- The Aqua Medic 1000 reactor is more than capable of supplying a 530 liter planted tank, when setup right.
- Mount the reactor after your filter or pump - it seems to increase the absorbtion efficiency of the reactor due the increased pressure in the reactor.
- Make sure that you have a flow around 1000 l/h in the reactor. This rate of flow seems to make it highly efficient.
- If you have trouble that the CO2 is sucked out of the bottom of the reactor, rather than bubble up into the reactor itself - remove the tubing inside the reactor, so that the CO2 bubbles out in the top of the reactor, rather than the bottom. This remedies the problem and does not seem to impact the efficiency of the reactor in any significant way.
- Do not swap the bioballs in the reactor for other media types. The bioballs are very efficient, when the reactor is set up right.
- The only flipside of the bioballs, is that it makes the reactor have the sound of running water. When it is behind closed doors in my aquarium cabinet, It is not loud enough to be bothersome to me. It might be to others though. Personal taste i guess.
I hope this can be useful for other owners of the Aqua Medic 1000 reactor.
Cheers