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Air at Night

2321 Views 15 Replies 9 Participants Last post by  Rex Grigg
I've got a 20g setup running a CO2 tank/reactor. My question is: Do I need an air stone at night for proper plant growth? I have enough O2 without it for the fish but just want to make sure I get the optimum parameters for the plants. I've read that people do it but has anyone actually witnessed an improvement?

Thanks >> bW
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Most people do it because at night, instead of releasing CO2, plants absorb it O2, which can lead to a deficiency in the water, and poison the fish.
I've got a 20g setup running a CO2 tank/reactor. My question is: Do I need an air stone at night for proper plant growth? I have enough O2 without it for the fish but just want to make sure I get the optimum parameters for the plants. I've read that people do it but has anyone actually witnessed an improvement?

Thanks >> bW
if you have enough O2 for the fish, do not run the air. You run the air if the CO2 concentration is too high for the ish and they get stressed. It does nothing for plant growth. If the fish are ok, then take it out altogether~
yeh. depending on how O2 sensitive your fish are you may want to. Most common fish are pretty hearty and are accostomed to our o2 deprived setups. however some wild caught are very particular.
I had a very nice African Tiger fish that got suffocated one night I forgot to turn my air on. Next morn. Dead fish = me out $300.
but if you turn off your CO2 at night, like I do, it is never an issue.
Stinks about your poor fish though :(
True. however this setup was before I used CO2. Was more for example that some fish are sensitive to lacking o2 conditions and night time plant consumption can reach levels that leave fish starved for o2.

As for the fish, I actually had 3 to begin with. :(
Aeration...

The only important thing here, aside the fish is to have a good concentration of CO2 in the morning before the light come up until shut off.
Personally I prefered using some aeration at night. After all our little bocals are far from getting the aeration of a natural setup. Good for fish, good for plants (they need it) and good for water quality.
don’t see any reason to not aerate if your able to keep CO2 to a certain level...
will this cause a large PH jump from day to night

with no CO2 my PH is 8.2
with 6.7

so will this jump back and forth daily and will this be a problem
From everything I have heard pH swings due to CO2 do not have an affect on fish. I run high CO2 during the day and aireate at night and have never had a problem with the pH swings.
Whoa Buckeyed.....

with no CO2 my PH is 8.2 with 6.7
That’s a big difference, I Think this is to much for the fishies.

How can that be!
:eek:

What’s your KH?
From everything I have heard pH swings due to CO2 do not have an affect on fish. I run high CO2 during the day and aireate at night and have never had a problem with the pH swings.
I'll second that.
My KH is around 5 to 6
my 50 lb co2 cylinder just ran out last week
it was three days before I could take it to the welding shop to fill it
and the SMS 122 controller was at 8.3 PH
6.7 is what I have my controller set to.
I do a every other month test with my 4.01 and 7.01 solution so
I think this is a good PH reading

my city water is at 7.7 to 7.9 all year
Lakewood Ohio, 44107

soil master select charcoal substrate
PH swing dont affect fish....

Because they are prisoner of our litlle tank an they cannot speak for their defense.
:iamwithst

Yes, PH swing affect fishs, they interfer with basics body function and causes stress that can be road to serious desease and death.
When the pH is artificially lowered using CO2 it has no effect. Normally pH changes are also accompanied by a change in the hardness and TDS of the water. This can put the fish into osmotic shock.

But when we lower the pH with CO2 the hardness and TDS are not affected.

Also many of our fish come from small streams that can have a huge change in pH, hardness and TDS with a normal topical rainfall.

Admittedly some fish are more sensitive to changes in the hardness and TDS than others. Many of the African Rift Lake fish require high hardness and TDS. This would normally be accompanied by a high pH. But you can use CO2 to lower the pH in the tank where these fish are located and they will not show stress, will continue to breed like the rats they are and eat everything in sight.

So the lowering of the pH which would normally cause a problem for these fish has no effect on them because there is no change in the TDS and/or hardness.

You need to really have a grasp of water chemistry to know why changing the pH with CO2 has no effect on fish. I'm hoping that this short missive will give you that knowledge.
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Hi rex
Thanks I will try this air stone this weekend
has anyone ever piped in a air line into the co2 reactor
since it will not be used during the nite time hours?
or is this way over kill.
Over kill. And you will end up with air in the reactor. CO2 dissolves pretty quickly. Air doesn't.

The whole idea with air is not to dissolve it but to actually create surface turbulence for better gas exchange.
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