How much co2?

Liakern

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Apr 26, 2009
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Im dosing ferts per EI method and 2x18watt t8 (6700,6500k) with medium planting. This is on a 55us gal tank BUT using my 29gal fixture(24in" tubes) both over the right side of the tank(with all my plants, left side is barren).

Should I just aim for 30ppm(average)co2 despite other factors or will this cause problems?
 

Philosophos

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36w on a 55 gal is pretty low, even over 1/2 the tank. Perhaps 3x the light over the entire tank would be somewhere in higher growth ranges.

For CO2, the answer to, "Do I need More?" is almost always YES. The CO2 levels are limited by the fauna, not the plants. The plants want atmospheric conditions up towards the 400ppm+ range.

If you don't have one yet, grab a drop checker. I may not look at mine much once the CO2 is adjusted, but it's good for starting up and diagnostic purposes.

-Philosophos
 

Liakern

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Apr 26, 2009
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So even with low lighting higher co2 levels will only ensure co2 is not a limiting factor and wont cause other problems like algea?

I ask because im tryn to get stable higher levels of co2 before I increase lighting to avoid an aweful algea out break.
 

VaughnH

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CO2 doesn't cause algae problems, as far as I know. Adding more CO2 than needed in a low light tank or portion of a tank just makes those plants grow faster and better.

A stable level of CO2 in the water isn't the goal. The goal is to have near the maximum the fish/shrimp will accept every day during the lights on time. If the level drops at night that won't trigger algae to start growing.
 

Liakern

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Apr 26, 2009
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Ithought fluctuating co2 levels triggered algea? Or just because co2 levels may drop to low causing a co2 limited condition, thus promoting algea?
 

Tom Barr

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Liakern;37966 said:
Ithought fluctuating co2 levels triggered algea? Or just because co2 levels may drop to low causing a co2 limited condition, thus promoting algea?

I think if you look at this from more light = more CO2 demand = more nutrient demand, it might help put it into perspective.

You do not have much light relative to the tank. But, adding CO2 will help.
You might not need 30ppm,. maybe 15-20ppm might be okay.
Who knows?

You can estimate somewhat, but that's about the best we can do realistically.
I'd shoot for 30ppm. You have more wiggle room(thus more stability) when you are able to add plenty of CO2 and have low light.

Should be pretty easy to add enriched CO2 to such a tank.
Regards,
Tom Barr
 

VaughnH

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scottward;37976 said:
What?!?!?!??

Yes it is!

No, if stable concentration of CO2 in the water were the goal, none of us could get away with shutting off the CO2 at night. That lets the CO2 concentration drop considerably every night, only to return to a high concentration the next day. That is hardly a stable concentration.

Maybe a better way to say this is to say we should not let CO2 be the limiting factor for plant growth at any time. Instead, we want the light to be the limiting factor. That makes us try for a "good" CO2 level every day during the photoperiod. But, it doesn't make us do anything about CO2 when the lights are out and the plants aren't even using CO2.
 

Liakern

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I think im goiin to make a needle wheel design... but have a more regular source of co2. I just really dont have the 180 bucks to go pressurized. (I have a daughter due july 28th, Danika Sage)

Only reason I havent gone with a needle wheel design or other diy ideas is because I have yet to see one that is not affected by the huge varying levels a diy co2 reactor has through out its life.

Thinkin of a way to keep co2 at a constant rate to avoid having to tweek co2 every day or worse come home after a long day to find my fish gasping be cause the yeast is peeking co2 generation. I got a couple ideas for this already Just tryn to make it all external aside from the powerhead.
 

Tom Barr

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If you sell plants, from growing them good and selling the cuttings....there's 180$ right there.

If you look on line, you can nab a regulator for 10-20$, and a valve for 20$. Tank for 40$ at a fire equipment supply. Now it's 70-80$, that's 3-4 plant sales on line.

You can be cheap, but focus on where you are cheap and still get good stuff, but for peanuts. Since you do not have $, you have the time to look for cheaper stuff etc.



Regards,
Tom Barr
 

Liakern

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The cheapest regulators I have found where 65 bucks plus shipping, ANY help on where to look for the regulators you are reffering to?
 

Gerryd

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Hi,

Have you tried e-bay or other online auctions like craigslist? Or some of the swap/trade forums on either this site or the planted tank.net?

Also, I seem to remember someone using industrial guages like for a welding setup.

Theoretically (I think) there should be no special setup for a fish tank as opposed to any other application, with the exception of the needle valve for more precise c02 flow.

Hope this helps.
 

Tom Barr

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Just look here:

CO2 regulator, great deals on Business Industrial, Pet Supplies on eBay!


eg:
http://cgi.ebay.com/Single-Gauge-CO2-Beer-Regulator_W0QQitemZ120437876192QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item1c0aa825e0&_trksid=p3286.c0.m14&_trkparms=65%3A12|66%3A2|39%3A1|72%3A1205|240%3A1318|301%3A0|293%3A1|294%3A50

These guys have everything all in one, but I like higher grade stuff, the reg and solenoid are likely fine and the Needle valve can be upgraded later.
65$

http://cgi.ebay.com/UP-CO2-Dual-Gauge-Electronic-Valve-Pressure-Regulator_W0QQitemZ250448204587QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3a4fe0532b&_trksid=p3286.c0.m14&_trkparms=65%3A12|66%3A2|39%3A1|72%3A1205|240%3A1318|301%3A0|293%3A2|294%3A50

Go to a Fire place and they sell tanks for 40$ or so, so now it's 100$ or so total.

Regards,
Tom barr