# Co2 bubbles per second in a reactor



## Aquarium_scape_n_fish (7 Oct 2017)

I have just converted from using an in tank diffuser to an external reactor to mix my co2 and eliminate the fizzy look.  Using the diffuser, my pressurised sodastream system ran at about 2 bubbles per second and turned the drop checker to an ideal lime green. Now I have the co2 running at 3, almost 4 bubbles per second through the reactor & the drop checker is firmly in the blue. I assumed that i'd have to inject less gas as the reactor is more effecient. Any ideas what is going on? What have I missed?
(Tank is a roma 90, 70l actual water, fluval 206 filter driving the flow in the reactor)


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## Zeus. (7 Oct 2017)

What media do you have in the reactor.
Also what inline atomiser are you using pre reactor?

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## Aquarium_scape_n_fish (7 Oct 2017)

The reactor does not use media and the spinning blades at the top dissolve the bubbles directly without an atomiser. That seems to be working ok. I can see the co2 hitting the blades and a minimal number of bubbles enter the tank. After increasing bps to 4, the drop checker is now light blue.
Maybe the bubbles from the old diffuser entering the drop checker were exagerating the co2 levels?

For the reactor, I have the 1000 model
https://www.sera.de/en/product/sera-flore-co2-active-reactor-500-1000/


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## Daveslaney (7 Oct 2017)

Check the output flow from your filter outlet. I used one of these reactors in the past they mix the co2 well.But i found they drastically reduce the flow from the filter. Maybe with the reduced flow its not distributing your co2 around the tank enough?
I had to use a powerhead below the filter outlet to get the flow up again.


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## Aquarium_scape_n_fish (7 Oct 2017)

The flow has certainly reduced but plants in all corners still have a swaying motion. I wanted to limit objects in the tank & a powerhead would look pretty ugly in there. I'd much rather have the bubbles back!! I can't picture how a powerhead could be completely external without causing issues to the filter flow. Is it possible to do?
Perhaps I'll just have to increase the bubble count and replace the gas more often


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## Zeus. (7 Oct 2017)

The other thing to bear in mind is the pressure of the bubbles. The lower the pressure the less volume they will have so less CO2. Not all diffusers/atomisers work at the same pressure. The Up inline atomisers I use to use needed a higher pressure to work than the JBL ones I currently use. The JBL ones have a much higher BPS because of the working pressure difference. So hard to compare CO2 injection rates with different atomisers, even the same atomiser with different heads of water will have a different BPS injection rate for the same pH drop.
I would ignore the BPS and just turn it up till you get the pH drop or colour change.

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## Aquarium_scape_n_fish (7 Oct 2017)

Zeus. said:


> The lower the pressure the less volume they will have so less CO2


That's a good point. I assumed that the larger bubbles being fully disolved would produce the same co2 as the sea of micro bubbles from the diffuser. I guess not 
I'm slowly upping the bps until i go green
Thanks


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## Daveslaney (7 Oct 2017)

Ok if your flows ok you are good. Mine was on a 300ltr tank so needed the flow. Cant remember the BPS i used on mine sorry. Be careful when you clean it though the nipple where the co2 pipe connects are prone to breaking off. I put a non return valve on the co2 pipe a couple of inch away from the reactor used to disconect pipe from there.


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## Zeus. (7 Oct 2017)

My DIY reactor is the same as Dave's, except I have twin ones, and a bypass too. So I can adjust the actual flow though the reactors from my Fluval FX6 which has an output of 3000litres per hour, so 1500l/h though each reactor. But I have found it still works well with low flow though the reactors, which I didn't expect. I fitted the bypass so I could maintain a higher tank return flow without the reactors restricting the filter output too much. Plus as an experiment.

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## Zeus. (7 Oct 2017)

Mine does have a massive BPS and over a 1.0pH drop way pass lime green on drop checker.


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## AverageWhiteBloke (1 Nov 2017)

Yeah you can't really compare bubble rates with anything, it actually means nothing other than to the individual. Same way of diffusing on the same tank you can tell whether you're adding more or less than you were before and that's about it. Even same tank same diffuser will vary depending if its clean. I've just bleach cleaned my inline diffuser and had to start all over again getting my co2 right. The difference was huge. I found with reactors I would need to start a bit earlier than usual in order to get the co2 fully dissolved. Add to that the DC is also running approx 2 hrs behind realtime you may find slower dissolving plus reaction time feels like it's not getting up to level as fast as it was. Atomisers don't really work off the same principle, you aren't really trying to dissolve co2 into the column although undoubtedly some will, the mist is designed to adhere to leaves which then readily absorb it rather than the plants trying to separate co2 back out the column it is dissolved in I guess. Very little of the mist actually ends up dissolved in the water although the smaller the bubbles the more surface area they have and more contact with the water on their brief journey from regulator to your living room ceiling. Around 90% of the gas we inject never ends up as plant mass and is just wasted. 

@Zeus. method is the most effective has it combines the benefits of both, minute bubbles with a large surface area being held in a chamber until fully dissolved. In big tanks it's also the most cost effective and big tanks have the cabinet space to home all the equipment. For smaller tanks we just put up with the loss using small atomisers and the small volume in the tank means they don't have far to travel before hitting some plants, Ideally if the bubbles are small enough the flow will keep them in suspension a bit longer.



Aquarium_scape_n_fish said:


> Maybe the bubbles from the old diffuser entering the drop checker were exagerating the co2 levels?



I would say this certainly would happen, we see plenty of microbubbles underneath the DC, no doubt they will enter it and affect the reading exaggerating it slightly, can't see why it wouldn't do that. I had the Sera 1000 reactor and really enjoyed not having the bubbles in the tank but I noticed it did slow down flow a bit. I also hate tank maintenance, especially filter so couldn't really be bothered undoing all the various bends and equipment. Got to the point I had to set myself a day aside to strip it all down and clean but I could never find that spare day so went back to simplistic as I could with inline diffuser.

My solution to the annoying fizzy bubbles.. I set co2 to knock off round about the time I get in from work. If a tree falls in a wood and no ones there to hear it and all that


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