Diy C02 Answer And Question...

[Eclecticoldsod]

First an answer for first timers like me. I set my system up with pop bottle, sugar, dry active yeast, and glass defuser. Not one bubble in a whole day, so I added more yeast, without result. Yesterday I chucked the lot and started again, but this time with fresh yeast from Sainsbury's bread department – millions of bubbles within a hour. Yippee! So, beginners, check your yeast before panicking – not all “active” yeast is as active as they claim is...

So much for cleverness – now to display my full ignorance.

What do I do with my set-up at night, when the lights go out? As Paul has asked [without an answer yet] will leaving it (very vigorous) in the tank after dark harm the fish? If yes, what do I do with it? Be polite...
Last night, not wanting to come down in the morning to a tankful of dead fish, I panicked.
I guessed that clamping the tube might lead to a vast explosion – is this right?
I guessed that disconnecting the tube and venting it into the room was not a good idea. Is this true?
So I unscrewed the cap and put the bottle out in the garden. But it has taken 4 hours after re-connecting to get going again – so I guess that was the wrong thing to do as well. Help please..!

 

[ulster exile]

Run an airpump on a timer during the night, then have it turn off an hour or so before your lights come on so that the CO2 levels have a chance to build up again - simple and hassle free! I certainly wouldn't try clamping the tube or anything like that

 

[Colin_T]

If you have the CO2 running into a room at night make sure the windows are open or some fresh air can get in. Also make sure that your dog or cat (if you have one) is not sleeping in the room because CO2 sinks to the ground and will suffocate anything on the floor.

If you leave the CO2 running in a tank without aeration during the night the fish will suffocate. The plants use oxygen when it is dark and use CO2 when there is light. When the lights are off everything uses oxygen and if there is no surface turbulence the CO2 levels will get too high and the fish will die.

Do as kilultagh suggested above and use an air pump on a timer.

 

[Eclecticoldsod]

Run an airpump on a timer during the night, then have it turn off an hour or so before your lights come on so that the CO2 levels have a chance to build up again - simple and hassle free! I certainly wouldn't try clamping the tube or anything like that

Thanks – I think... Are you saying that an air pump in the tank nullifies the CO2, because I run an airstone 24/7, so have been running both together during the day – should I not be doing that?

P.S. Is there a board prize for displaying a staggering amount of ignorance..?

 

[Colin_T]

If you are using CO2 during the day then there should be minimal surface turbulence. Any sort of surface movement will help the excess CO2 to escape and that defeats the purpose of adding it.
At night you want surface turbulence to help get rid of the excess CO2 and allow more oxygen into the water.
Turn your pump off during the day and have it on at night. Use a small water pump to circulate the water around the tank but have it well below the surface so it doesn't agitate the surface water.

 

[Eclecticoldsod]

If you are using CO2 during the day then there should be minimal surface turbulence. Any sort of surface movement will help the excess CO2 to escape and that defeats the purpose of adding it.
At night you want surface turbulence to help get rid of the excess CO2 and allow more oxygen into the water.
Turn your pump off during the day and have it on at night. Use a small water pump to circulate the water around the tank but have it well below the surface so it doesn't agitate the surface water.

Thanks Colin, and Kilultagh! Light finally dawns on my poor, sad old brain. I understand now.
You guys on this board are amazing – no question to dumb to answer, nothing too much trouble. I am so glad that I found you great people..!

 

[ulster exile]

We all have to start somewhere - you should read some of my posts! Actually, don't read any of my posts