HC Surviving Without Compressed CO2

Philosophos

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It looks like Diana Walstad has managed to
pull off HC for 10 weeks of submersed growth in a DSM NPT.

Does this mean that under low light, HC may not require compressed or even DIY CO2 so long as it's established? This test is young, but I'm keeping an eye on it. It's possible that high CO2 is only necessary to establish rooting behavior, or that CO2 and high light pushed growth far enough to root submersed HC.

If it doesn't take compressed CO2 for HC, then this is a big thing for the hobby. I don't want to be premature in advocating anything, but it's at least worth keeping an eye on. I've got a number of questions as to the details right now, but having someone this big in the hobby claim success isn't a small thing.

I'm guessing that traditional NPT won't do if this works; I've had HC uproot from excessive mulm filtering down when I didn't maintain the tank well. Still, low tech with even monthly upkeep for HC would be neat. This would fit most aquarists schedule given that "30% once a month" is almost mantra to new hobbyists doing fish-only tanks.

I've got a lot of questions on this subject. I'm hoping discussion will reveal a bit more.
 
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dutchy

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Also Tropica (www.tropica.dk) reports that HC can be grown without CO2. QUOTE: Like in most other cases, extra vivid growth is obtained by adding CO2 but the beautiful oxygen bubbles are often formed also without using CO2 enrichment.

Regards,
Dutchy.
 

Biollante

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An Observation

Hi,

Honestly, with lower light I am beginning to think pressurized CO2 may not be necessary, at least at our current levels. :confused:

I suspect a couple of things are in play here, not the least of which is the use of ammoniacal fertilizers early on. This is something I have noticed in my messing about with substrates. :)

Taking aquatic plants that are usually in there emergent form and allowing them to adapt and develop prior to submerging solves many problems before they start.

Though it seems to anger many, I have noticed (I know, I know, I am too stupid to know anything about controls :eek:) that in lower light in environments, additional CO2 can be supplemented by breath, aeration and water changes. ;)

Biollante
 

Tom Barr

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Philosophos;47154 said:
It looks like Diana Walstad has managed to
pull off HC for 10 weeks of submersed growth in a DSM NPT.

Does this mean that under low light, HC may not require compressed or even DIY CO2 so long as it's established? This test is young, but I'm keeping an eye on it. It's possible that high CO2 is only necessary to establish rooting behavior, or that CO2 and high light pushed growth far enough to root submersed HC.

If it doesn't take compressed CO2 for HC, then this is a big thing for the hobby. I don't want to be premature in advocating anything, but it's at least worth keeping an eye on. I've got a number of questions as to the details right now, but having someone this big in the hobby claim success isn't a small thing.

I'm guessing that traditional NPT won't do if this works; I've had HC uproot from excessive mulm filtering down when I didn't maintain the tank well. Still, low tech with even monthly upkeep for HC would be neat. This would fit most aquarists schedule given that "30% once a month" is almost mantra to new hobbyists doing fish-only tanks.

I've got a lot of questions on this subject. I'm hoping discussion will reveal a bit more.

I spoke with her in Australia, Glad to see she did a nice test tank with HC.
I think the conclusions are fairly good throughout the pdf there.

Stem plants do compete strongly for CO2 with HC etc. This we see with CO2 enriched tanks wher ethe CO2 rate drops off.
The floating plants do not compete however.

I see this in my non CO2 tank with the Bolbitus that's submersed, and with lots of emregent Water sprite etc.

A non CO2, non Excel dosed planted tank can have most any species, but the competition factor for CO2 mostly is the problem.
I'd speculated this about 10 years ago, when I grew Gloss and Hairgrass in oine such tank.

These days, I think it's fairly clear the role CO2 is playing, and why and how light/CO2 affect such tanks, as well as CO2 enriched tanks, they are more similar than many assume.

Regards,
Tom Barr
 

Tom Barr

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Dan, I think HC and non CO2 methods do work, but folks need to realize that the light is blocked by floaters which do not compete, there's little competition for CO2, no stems etc.

Many want that, or want to add lots of of species together.

I think these issues will cause the most failures, not reading between the lines and the entire story.


Regards,
Tom Barr
 

Philosophos

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Good point there Tom; I wasn't even thinking of how little CO2 might go into a tank like that. I suppose this probably means a whole lot of iwagumi NPT's in the future then.

What about using air stones as Biollante mentioned? Wouldn't heavy oxygenation provide a more constant renewal of CO2, even if the long-term buildup isn't as high? I've come to rely on them in my lower tech tanks where CO2 seems to be limiting, and it seems to help.

Dutchy, that Tropica bit mentioning pearling without CO2 is interesting. I wonder how balanced the light/CO2 is in order to do that as I rarely see pearling without CO2. Your link brought me to the homepage; you've got to use "view frame" to get a working link from them. Here's the article
 

shoggoth43

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As long as the plants are putting out O2 at a rate higher than the surrounding water can absorb it you'll get pearling. Having ready sources of CO2 in play will certainly make it easier for the plants to get in high gear to do this, but it's not strictly a requirement and it probably won't be as sustained an event in comparison to pressurized CO2. An excel dosed tank should also be able to do this as an example but a nondosed tank should theoretically be possible to pearl.

-
S
 

Tom Barr

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Philosophos;47176 said:
Good point there Tom; I wasn't even thinking of how little CO2 might go into a tank like that. I suppose this probably means a whole lot of iwagumi NPT's in the future then.

What about using air stones as Biollante mentioned? Wouldn't heavy oxygenation provide a more constant renewal of CO2, even if the long-term buildup isn't as high? I've come to rely on them in my lower tech tanks where CO2 seems to be limiting, and it seems to help.

Dutchy, that Tropica bit mentioning pearling without CO2 is interesting. I wonder how balanced the light/CO2 is in order to do that as I rarely see pearling without CO2. Your link brought me to the homepage; you've got to use "view frame" to get a working link from them. Here's the article

Well the CO2 demand by HC is really pretty low. You still do pretty well using Excel dosing with HC also.
So absolute values need not be high, but if there are other plants that have more biomass and demand, are closer to the lighting........then they will have more access and uptake, leaving the HC in the dust.

Few plants are not closer to the light than HC.
It's the runt of the aquatic plants and farthest away from the light. It does not need more light, it just needs less competition for CO2.

I've shown several times that it does well at low light: 40 micromoles can produce really nice lush carpets with CO2.
Without CO2? I'd expect more light may be required, but, also less stability and more algae risk.

I think the aeration would reduce the CO2 in the start of the day. Then add it late.
So try adding aeration say after 2-4 hours. then stop 4-6 hours before the lights come on.

Regards,
Tom Barr
 
C

CL_

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I had hc growing just fine in my non-co2 tank. 2.5 gallons, 15 watts of light. AS powder for substrate. 1 mL of excel every other day. Things were growing great until my cat found a way to pull the tank off of my desk. This was about 18 mos. ago I think...
The last picture of the tank before it broke.
DSC00005.jpg

I've also had a good farm of hc growing in a sealed jar with 3 inches of clay from my yard topped with inert black sand substrate. I haven't opened the jar in at least two years believe it or not. It sits a few feet away from a south facing window. No algae at all that I can see.
 
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C

CL_

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milesm;47313 said:
Chris,

nice tank. very strong cat.

Thanks. He was jumping up for a drink and the tank was at the edge. Grabbed the top of the tank and pulled it down when he tried to grab the edge of it as he was jumping up there.
I was not happy with him to say the least.