Co2 Into Filter Intake Question?

[DaveW]

As of yesterday, I'm now injecting the CO2 straight into the intake of the filter. It all seems to be working, but the CO2 levels have dropped . I had the CO2 running on a Nutrafin ladder with around 55 bpm to give me a CO2 level of 45ppm (because of an algae problem). I didn't change the setting on the regulator, just switched it off. I checked the CO2 levels last night and it was 29ppm, which is not bad. And thought it might take time to build up as I cleaned the filter and new sponge etc. The CO2 has been running for a couple of hours this morning and the co2 level is only about 15ppm. I was under the impression that running the CO2 straight into the filter would dissolve almost 100% of it? Have I got some thing wrong, or will it take a little time to settle in?
Any help will be gratefully received!

 

[DaveW]

Well I've just did a test and the CO2 is back up to 45ppm as it was before.
It looks like it was just a matter of time.

 

[DaveW]

I check the CO2 again, 4 hours after it came on. The level was only 29ppm, not the 45ppm that I what at the moment. I check it again when I came home tonight and it's up to 45ppm. So it seems it takes over 4 hours to get to the required level .
Is this normal for this type of set up?
Is this stable enough?
I'm really not sure if this method is working right. Please advise if you can!

 

[zig]

hmmm just started doing this myself today but the CO2 was on for ages beforehand being diffused by a ladder, but if it takes 4 hours to build up to required levels though that aint going to be much good and the ladder may have to go back in again, ow well thought i had gotten rid of it, what filter are you useing? im useing an eheim 2215 but have only been doing this for a few hours at this stage, so i dont exactly know how long it takes to get going.

 

[DaveW]

I have an Ehiem 2213. I might be doing some thing wrong? And you might have better luck than me.
I'm keeping it going 24/7 at the moment to keep the high level.
I'm thinking of possible getting a glass ceramic diffuser. But I love the idea of it going thorough the filter.

 

[KrayzieVanh]

I have an Ehiem 2213. I might be doing some thing wrong? And you might have better luck than me.
I'm keeping it going 24/7 at the moment to keep the high level.
I'm thinking of possible getting a glass ceramic diffuser. But I love the idea of it going thorough the filter.

I am using the Aqua Clear 50 filter. I get 28 PPM of CO2. That's borderline for me since I have fishes. For such a high PPM you probably don't have fishes in your tank

 

[DaveW]

Yes, I have fish. Check my signture. They are still very happy with the high CO2.

 

[KrayzieVanh]

Yes, I have fish. Check my signture. They are still very happy with the high CO2.

So high CO2 isn't a problem for fishes? I guess I won't have to worry about disconnecting the CO2 at night then!

 

[DaveW]

If you turn it up slowly and keep a close eye on your fish it should be OK.

 

[DaveW]

hmmm just started doing this myself today....

How are you getting on with it Zig?
Mine seems to be stable with it going 24/7. But I'm still thinking of going over to a glass ceramic diffuser.

 

[zig]

hmmm just started doing this myself today....

How are you getting on with it Zig?
Mine seems to be stable with it going 24/7. But I'm still thinking of going over to a glass ceramic diffuser.

TBH Dave i havent been to worried about it, im having some problems with my lights at the moment and waiting for a new light unit to arrive so at the minute im only running on 1.4 WPG instead of the normal 2.8 WPG and the uptake of CO2 by the plants is not that much due to the lower light levels so its very hard for me to judge, yesterday i checked my levels and they were at 20ppm CO2 so i upped the bubble rate and checked it 2 hours later and the CO2 was now 30ppm and the ph had dropped by.2, so i just kept it there for the rest of the day, how long it took to get there im not quite sure it might only have taken an hour, but i was sort of guessing the approximate bubble rate to achieve it.

I will do some proper tests in the next few days to see exactly how it is working, i might go with a glass diffuser but im still sceptical as to how efficient they are, i will have to check around first of all, but i honestly cant see why the CO2 directly into the intake shouldnt work this would be my preferred option.

What way have you got your spraybar pointing or what way do you use it?

And what sort of surface agitation do you have?

And how big is your tank? I know its 33 gallons is that US or imperial?

 

[George Farmer]

As you know I have my CO2 direct into the inlet of my 33G.

I used to run around 45 BPM 24/7 - this gave me 25-30ppm CO2.

Now it's a little more complex -

I manually turn off CO2 at lights out or just before.

At around 7am I turn on the CO2 and set it at 30 BPM (I also dose my macros/micros at this time too).

At midday (lights on) when I get home for lunch I set it to 60 BPM.

The theory is that the CO2 level builds in the morning from 7am to midday, but not too much.

I've found this to give me stable CO2 during lighting hours at 30ppm with the benefit of not wasting CO2 like I was with 24/7 injection.

It sounds like a lot of hassle but it takes moments to do, it's part of my daily routine along with the fert dosing and fish feeding at lunch.

Eventually I will invest in a solenoid and have the CO2 still come on before lights to get the stable CO2 during lighting.

When I'm away I just leaving the CO2 on 24/7 at 45 BPM as before.

I also run 10 hours photoperiod straight now rather than having a siesta, so far so good, the plants are pearling much more at the end of the day now.

 

[Ste_J]

George thats some routine you have there!

I was looking at venting straight into the eheim but after some reading found that this method often led to an increase in noise from the filter? Not sure as to how true this is and only you guys could comment. At the moment I'm trying the powerhead design which seems to be working quite well although it does not give the fine mist through the tank that I was hoping for, today I have recieved the Azoo which I intend to position under the powerhead intake, hopefully this should allow for the fine bubbles to be spread though the tank whilst giving the plants an increased flow - I believe that this increases the amount of CO2 that they are able to take in ?

Not got a bubble counter with my current setup although the PH monitor shows that the CO2 was ranging from 30 - 38ppm as the PH changed through the day. Just looked tonight and the rate has reduced although more plants are starting to pearl so I suspect that the CO2 intake has increased - this coincides with a change to fert dosing.

So have you found an increase in filter noise? If the Azoo and powerhead don't give me what I want I'll try the CO2 direct into my eheim - using a vertical spraybar which alos improved the overall flow distribution.

Powerhead and CO2 is currently controlled by a solenoid to run with a straight 10hr lighting session

 

[George Farmer]

I realise my routine sounds rather high maintenance but it really only takes a few moments every morning and lunch. One positive aspect to adjusting the CO2 output manually is the automatic compensation for ambient temp. effect on the CO2 pressure and consequent bubble rate.

I find there is a little noise from my filter but unless the room is in silence then one doesn't notice it, and even then it is bearable. A friend of mine has a 160G reef tank in his living room - much more noise, beleive me!

I also run a vertical spray bar. Occasionally my filter spits out a fine stream of CO2 bubbles that disperse throughout the water column very effectively.

 

[zig]

So far for me its totally silent (only second day trying this method) but my bubble rate is low, dont know how it would be if i doubled the bubble rate.

I wonder what the situation is as regards people that use inline reactors, presumably it takes just as long for the build up to occur, as its exactly same method but yet (or is it? cant see how its any different really) you dont ever hear of our American friends on PT complaining of this buildup time lag, hmmm but there again i guess most of them are using ph controllers along with solenoids so its not an issue for most of them as the CO2 just switches on as needs be.

Ste the experiments sound good keep us informed, you should try the diffuser under the spraybar without the powerhead and see how that works as well.