CO2 loss or bad dissolution?

el_tubaron

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Sep 22, 2008
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Hello,

This is my first post in this forum, and after reading a lots of post i dont find the answer to my problem.

so first my setup (with 5 weeks):

The Cube

Dim: Cube with 46cm x 46cm x 46cm (96L)
ligth: HQI 70w 5200K
substrate: Fourite
CO2 pressurised 1 b/s
and the parameters:

pH: 7.2
kh: 6
GH: 9
NO4: 5ppm
PO4: 0.5ppm
Fe: 0,5

And of course the photo :D

the_cube_05_01_2009.jpg


And now my question, I cant dissolve more than 12ppm of CO2 (pH: 7.2 - kh: 6) for example with 1b/5s i have 12ppm and with 1b/s i have the same 12ppm, I don't understand why??
My reactor for the dissolution is a vortex reactor (DIY) and it seem working with no problem (at list I see that all co2 that is inject in the reactor dissolve).
the in take an out take are in the water (for reducing the turbulence), so I don't see why I can get 20 or 25 ppm... 1b/s isn't in off for a 100l ?
Or better what can reduce the dissolution of the CO2?

PS: sorry for my poor engish but my native language is portuguese :)
 

tinkerman

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Dec 8, 2007
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How are you getting your results drop checher or ph/kh table? If your using the ph/kh the wood in your tank will mess with your results.
 

VaughnH

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You are trying to measure the amount of CO2 in the water by measuring KH and pH, and looking up the ppm of CO2 in a table. That doesn't work for an aquarium. It does work if you use distilled water with only carbonates added to it, but the water in our aquariums has lots of other ions in it. Your tank, which is very beautiful, has a lot of wood in it, so the water will have tannins in it, and that lowers the pH, making the KH/pH/CO2 relationship incorrect.

If you buy a drop checker and fill the bulb with distilled water which has just enough sodium bicarbonate in it to give 4 degrees of KH, plus a couple of drops of bromothymol blue pH reagent, and put it in the tank, after about 2 hours the water in the drop checker will be green if you have about 30 ppm of CO2 dissolved in the tank water. That is the most accurate way we have to measure CO2, short of spending thousands of dollars for a specialized CO2 measuring probe.
 

el_tubaron

Junior Poster
Sep 22, 2008
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Well, the wood.... I have never thought of that, but I'm sure that's it, because it's a really big piece of wood. But the PH is 7,2 even whith the wood and the CO2, so maybe my CO2 concentration is ok.
I'm gonna by a drop checker and do the 4 KH solution with the bromothymol blue pH reagent.

well for now, I'm gonna stay with the 1b/s until I have the drop checker... and pray :)

PS: thanks a lot for your quick reply .

Just one more question that has nothing to do with this (I think so) in 2 weeks 7 fish jumped out the tank (like a kamikaze :) is this normal? (its my first open tank)
 

tedr108

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re: Kamikaze fish

It depends on the type of fish you are talking about. Some are natural jumpers, like hatchet fish (and full grown SAEs for me, at least) and need a cover. Some non-jumpers will jump when they are stressed and unhappy because of water parameters or perhaps other reasons.

If you let people here know what type of fish jumped, they will surely be able to tell you if it is normal or not. In your tank, I can only see Rummy Noses and Otos. Neither one of these fish ever jumped from my tanks.

Your tank is very beautiful, by the way -- wish I could scape like that!
 

VaughnH

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I had a Yoyo Loach do the kamikazi trip a few months ago. I just assumed he sensed the river, which is about a quarter mile away and was aching to swim back to Asia. Unfortunately, he didn't leave a note.
 

el_tubaron

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Sep 22, 2008
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tedr108;32264 said:
re: Kamikaze fish

It depends on the type of fish you are talking about. Some are natural jumpers, like hatchet fish (and full grown SAEs for me, at least) and need a cover. Some non-jumpers will jump when they are stressed and unhappy because of water parameters or perhaps other reasons.

If you let people here know what type of fish jumped, they will surely be able to tell you if it is normal or not. In your tank, I can only see Rummy Noses and Otos. Neither one of these fish ever jumped from my tanks.

Your tank is very beautiful, by the way -- wish I could scape like that!

Well, the Kamikases fish was 4 Rummy Noses and 3 guppy, the temp is 25ºC the water parameter seems to be ok...

may be the tank is to small for the Rummy Noses but for the guppy I think its ok...

VaughnH: It coud be that, I have a river realy near my house :D


ps: today another one, 5 Rummy Noses and 3 guppy .... any ideas? :(

Cumps
Victor Pinto
 

VaughnH

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I have several guppies in my 45 gallon, open top tank too. I can only remember one who jumped out last summer, when I was away for a week. You have something unusual going on, I think. Is the tank overcrowded with fish?
 

el_tubaron

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Sep 22, 2008
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VaughnH:

VaughnH;32306 said:
I have several guppies in my 45 gallon, open top tank too. I can only remember one who jumped out last summer, when I was away for a week. You have something unusual going on, I think. Is the tank overcrowded with fish?

I dont think so, because I have 2 octos 1 guppie 5 Rummy Noses 2 snails neritina and about 10 red cherrys in a 25g tank.

Here a photo taken 29 12 2008, we can see 7 Rummy Noses and 3 guppies
the_cube2_29_12_2008.jpg


I have no ideas what is the problem? the direction of the out take? :confused:

Cumps
 

tedr108

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SuperColey (AC) makes a good point...

1 bps would normally not be able to overload a 25G (100L) tank with CO2. However, it seems you reduced your surface agitation to try to reduce CO2 off-gassing. Lack of surface agitation has the other side-effect of reducing the oxygen in the water. Tom and co. recommend a decent amount of surface agitation to keep a tank oxygenated ... if you need greater CO2 concentration, you would increase CO2 bps, not reduce normal surface agitation. With decent surface agitation, I would think that 1 bps, maybe 1.5 bps, would keep enough CO2 in your tank. I was able to keep a 50G tank at 30ppm CO2 with 3 bps, and I was leaning toward too much surface agitation.

Another question for you is: Do you run your CO2 reactor at night? Plants do not use CO2 after lights out and instead go to oxygen. The highest concentration of CO2 and lowest concentration of oxygen will happen at night, if you run your CO2 at night. If your fish are only jumping at night, that may be a clue.
 

el_tubaron

Junior Poster
Sep 22, 2008
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tedr108;32329 said:
SuperColey (AC) makes a good point...

1 bps would normally not be able to overload a 25G (100L) tank with CO2. However, it seems you reduced your surface agitation to try to reduce CO2 off-gassing. Lack of surface agitation has the other side-effect of reducing the oxygen in the water. Tom and co. recommend a decent amount of surface agitation to keep a tank oxygenated ... if you need greater CO2 concentration, you would increase CO2 bps, not reduce normal surface agitation. With decent surface agitation, I would think that 1 bps, maybe 1.5 bps, would keep enough CO2 in your tank. I was able to keep a 50G tank at 30ppm CO2 with 3 bps, and I was leaning toward too much surface agitation.

Another question for you is: Do you run your CO2 reactor at night? Plants do not use CO2 after lights out and instead go to oxygen. The highest concentration of CO2 and lowest concentration of oxygen will happen at night, if you run your CO2 at night. If your fish are only jumping at night, that may be a clue.

good point here, well to I never close the CO2 at night and 2 guppy and 3 noses jump out at night.... maybe and the other before the light on in the morning. I'm gonna reduce the CO2 to 1b every 3s and put the out take up to the surface to have more agitation. I will wait and see....

Cumps
Victor Pinto