[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[APD] Re: CO2 measurement with bubble counters

>> I think a bubble rate counter would be an easier method and close to
>> the same range of this.
> So then I determine the correlation between CO2 level (as measured by
> offline KH and pH levels) and bubble rate for my system? So then if
> bubble rate is okay, CO2 should be okay?

Pretty much, you'll see some variation in the bubble rate if the CO2 dosing
drops off or increases etc. At least enough to check the CO2 good....which
we _often neglect_ to do.
>> But a pH monitor would be better... if you want constant CO2
>> determination.
> I'd love a pH probe, but definately can't afford one. That's why the
> cheap and nasty CO2 indicator appealed to me in the first place.

I think a bubble counter would be better overall. I did not answer your
question but gave an alternative that I think might be easier/more suitable
for you. 
>> Folks seldom use these CO2 indicators anymore but they do alright.
>> Dupla and a couple of other companies made them. Folks tried
>> everything to DIY a Dupla component. But many you did not need. This
>> was one of them IMO.
> I realise that this type of thing is not a necessity and cannot replace
> offline measurements, but thought it might be good as any early warning
> sign if CO2 levels got too high (although after reading a few of the
> recent posts I'm not to sure what level of CO2 would be considered "too
> high"). Maybe I just won't bother and go for the bubble counter thing
> instead.

Generally over 30ppm or so. Some get away with more, some have trouble at
30ppm etc but okay 20-25ppm. There's some error built in to 20-30ppm
recommendations for this very reason.
>> But a simple spreadsheet could easily convert folk's routines into a
>> weekly ppm rating if that's what you are after.
> Yep, I sometimes do calculations like this to get a better
> understanding of what other people are adding to there aquariums. But
> what works for me may not for others, so I guess I'll just keep doing
> the calculations myself.

If it helps you to understand it better, there are general ranges folks have
established though. You can try other mixes, but it's not a bad place to
start out at and vary each variable one at a time to gauge each parameter's
effect on the system/plants. Then you can move up to two or more variables
at a time and so on.
>> I've come up with fairly decent daily usages for NO3, PO4 at least
>> what I would consider primarily plant uptake and a good CO2 level
>> which applies to all CO2 enriched tanks, low, med, high light etc.
> This sounds interesting, can you please elaborate. I'm guesstimating
> about 0.2ppm phosphate per day and 1.25ppm nitrate per day for my
> system.

You'll need good test kits if you want useful information from these.
Lower light systems might take up the levels you mentions, generally, I see
3-4ppm of NO3 a day, .3-.4ppm of PO4. About 10:1 N:P ratio. Some systems
might remove more/less depending on plants species/degree of starvation in
the plant tissues etc.
>> The others are all in fairly excess and hence their dosages/uptakes
>> are estimated.

> So as long as you're not seeing deficiency symptoms for K, Mg, Fe, and
> traces, the levels/dosage is probably okay?

As long as you are knowingly adding more relative to what the N:P uptakes
rates are, their levels are not as dramatic.

Adding CO2 is very dramatic. Adding NO3 and/or PO4 is semi dramatic, K+
so-so, adding Boron will not be something easy to see right away. Traces are
harder to tell and take 3 weeks or more etc.

So look for the things that are easiest to see and note first, then move on
down the line. 

The line: light, CO2, NO3, K, PO4, traces.
These are the main things folks add generally beside some that vary their

Tom Barr 

> Thanks again for your reply Tom
> Clint Brearley
> Melbourne, Australia

Aquatic-Plants mailing list
Aquatic-Plants at actwin_com