Tom's internal venturi reactor

Tom Barr

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Good, so the BBa and algae are on the run?

Why, would you suspect the pearling is sooner(thus more plant growth) vs the other method?

Regards,
Tom Barr
 

milesm

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Oct 18, 2006
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there is a significant confound to my results :eek:

i now have co2 injecting about 1 hour before the lights come on; prior, it was simultaneous. so my conclusion of earlier/greater pearling is open to debate, although the aesthetics of fewer bubbles is not, and that in itself is good enough for me. (maybe with fewer co2/o2 bubbles flying around in the tank makes pearling more evident?)

nonetheless, i think the venturi reactor gets the co2 into the water column as mist and dissolved. i don't have a drop checker so i can't say how much co2 is present in the tank but the plants have never looked better.

bba and other algae are all but absent, although i still get some gsa on the glass. i've been using fleet's enema, and have been dosing it haphazardly. i ordered k2po4 from greg so i should be able to get a handle on gsa.

thanks for your help.

ps both methods were used with pressurized co2; same bubble count.
 

Tom Barr

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I think if you add KH2PO4 3x a week, you'll be fine.

Yes, you cannot say with 1 hour prior to the lights coming on.
But you can see a difference in ther plant health/algae and growth.
That is significant.

Folks can go back and try adding the CO2 prior etc 1 hour before also and still have good result mine you, but there is a difference that is significant you can see in the method.

It's not just belief.
You just do not get the same results with other treatments time and time again and the differences often are large, not a subtle minor thing or improvement that can be attributed to a number of other things that you can account for, repeat over and over again and try.


Regards,
Tom Barr
 

qsaark

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Feb 11, 2007
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Hello,

This is my first post in this forum. Following Tom's guidelines, I made my own CO2 diffuser. Apperently it is working very fine. Some tiny bubles are still on the run, but generally it is ok. I have used a long and rather thin cylinder. Otherwise, I guess it is almost as described in this post. Another feature is the attachment of the diffuser to an internal filter that saved me some bucks. I am using it in a 10 gallon tank so probably OK.

powered CO2 reactor-2.jpg
 

Tom Barr

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This works fine.

Some improvements to the design might be to extend the rigid tubing in the venturi loop down about 2" from the top of the clear tubing.

This way you'll get 100% dissolution till about 1-4 hours into the day.
Then once enough CO2 had built up, the venturi will kick in and start pumping out the gas mist into the tank.

If the bubbles are not blown out, you can extend the length of the CO2 in rigid tubing also to about 1/2 from the bottom of the main clear tube.

As long as the CO2 bubbles are not blown out...........the lower that is the better.

Regards,
Tom Barr
 

Tom Barr

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the other thing you can do to the venturi loop rigid tubing coming into the Reactor tube, melt and pull it out a bit at the tip, this will suck in smaller bubbles/tear the CO2 up better, but............it can clog easier as well, always a trade out.

Regards,
Tom Barr
 

qsaark

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Feb 11, 2007
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Tom Barr;14375 said:
the other thing you can do to the venturi loop rigid tubing coming into the Reactor tube, melt and pull it out a bit at the tip, this will suck in smaller bubbles/tear the CO2 up better, but............it can clog easier as well, always a trade out.

Regards,
Tom Barr

Tonight I'll try to improve the design as per your suggestions.

By the way, what if CO2 is directly injected into the pump's venturi?
Since some tiny bubbles are still escaping, is it OK to put a 1" thick sponge near the exit?
 

VaughnH

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One of the advantages of this design is that tiny bubbles do escape, giving you some CO2 mist in addition to the dissolved CO2. Unless you have DIY CO2 it isn't important to have 100% of the CO2 dissolve into the water. Pressurized CO2 is cheap. In other words, don't put the sponge in there!
 

qsaark

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Feb 11, 2007
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qsaark;14395 said:
Tonight I'll try to improve the design as per your suggestions.

By the way, what if CO2 is directly injected into the pump's venturi?
Since some tiny bubbles are still escaping, is it OK to put a 1" thick sponge near the exit?

Is it possible to use a venturi with two inlets to address the clogging issue?
 

qsaark

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Feb 11, 2007
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Tom Barr;14375 said:
the other thing you can do to the venturi loop rigid tubing coming into the Reactor tube, melt and pull it out a bit at the tip, this will suck in smaller bubbles/tear the CO2 up better, but............it can clog easier as well, always a trade out.

Regards,
Tom Barr

To avoid clogging, can we use a venturi with two inlets?
 

Tom Barr

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Yes, you may use two venturi's if you wish. But just use a larger hole in that case.

No sponge!
Note the effects on plants closer to the outflow.

Regards,
Tom Barr