DIY CO2 for Plants Using...a Straw?

[lotus flower]

Hey, guys!

So, I made the mistake of buying some sword plants without a source of CO2 readily available during my fishless cycle. Setting aside the issue that I will be leaving town for 2 weeks soon, I've been reading about lots of "home-brewing" techniques using yeast and baking soda, and then I read about one guy who exhales into trash bags and then pumps his own CO2 into his aquariums using an air pump INSIDE the bag and an airstone to break up the bubbles in the tank.

What I'm wanting to know is, given that my tank is only about 2.5 gallons, could I just exhale through a plastic straw into the tank twice a day for, say, 2 minutes at a time and inject CO2 that way? I mean, it would already be broken into bubbles and everything. Plus, it's oxygenating and adding nitrogen at the same time.

Human exhalation is approximately 3.5-5% carbon dioxide, from what I've read. I don't know--it sounds feasible to me. I had a very small sea-monkey tank survive for months with me aerating it only with a large turkey baster for oxygen twice a day. This seems similar, as it is just for the plants and I already have a filter and airstone bubbling oxygen into the tank.

What do you guys think? Anyone ever tried something crazy like this before?

Thanks!

[Sarkazmo]

Ummm... I think you'd pass out. Just make a DIY CO2 system with a couple 2ltr pop bottles, some air line tubing, a one way valve, and an air stone.

Sark

[lotus flower]

ROFL, Sark:hmm3grin2orange: ! And I wouldn't stop until I did, too!

Thanks for your input!

[lotus flower]

Oh--and anyone have any idea how long the tank can go without CO2? Bad weather here and can't do it tonight--plants just came from the store today. I figure I can set up the bottles tomorrow.

[HeatherB]

I had Amazon swords that I got from the petstore when I first started fishkeeping, like, 3 years ago. I dosed with nutrients like, FloraMax from Tetra, but other than light they got nothing else. They are still alive today.

I recently switched to Co2. It is a great difference. Your plants will be fine- just not as green, lush as they could be. Waiting a day or two won't hurt. They may 'melt' a little until they get accustumed to your tank- and also maybe after you get the co2 in it. But they will come back beautiful!

I made a simple co2 by drilling a hole in a 2 liter bottle cap, pulling airline tubing thru it. (only about a half inch or so) Then you fill the bottle with I use about 2 cups sugar, 3/4 tsp of Rapid Rise yeast and warm water up to the curve of the bottle. Cap it, give it a good shake and slap an airstone on the other end of the tubing.

I didn't even worry about a check valve because my bottle is currently sitting on top of my tank. Works great. I will however eventually invest in one of those 'ladder style' Co2 things like Hagen makes. I have one, and it works great- keeps the bubbles in contact with the water longer.

[Lady Hobbs]

I don't use CO2 in any of my planted tanks. So the growth may be slowed down but for me I don't care because I have to trim them all back once a month anyway.

[lotus flower]

HeatherB--I was looking at those Hagen Plant Gro systems. They look promising, but kind of pricey.

Lady Hobbs--That's good to hear that you can get by without. My problem is, when I told the guy at the LFS that I had a 2.5 gallon tank, I asked for Java fern. They were all out, so I asked for another low-light tolerant plant. He said the Amazon sword. So, making sure to tell him about the size of the tank, I went off to pick up some fertilizer on the other side of the store. I get up to the front and there's a huge plant sitting there! I thought it would fit, but it's quite a tight squeeze. So, needless to say, I don't need any more growth than what will keep this plant alive...I'm already going to be pruning every couple weeks!

And I have no idea how to even prune an Amazon sword... (blush)

Thanks, guys. Anyone have pruning ideas?

[smaug]

Co2 isnt really need for decent growth with sword plants.Mine were overgrowing the tank with nothing added at all toward the end [yesterday:hmm3grin2orange: ].

[lotus flower]

I've got some wisteria in there now, as well...so I'm doing a very small CO2 injector, using my knowledge of fermentation from microbiology lab! (actually, just the knowledge that a glass container won't shatter!). I found one of those oil/vinegar bottles at Wal-Mart, like you use at a restaurant with the metal pour-spout, and it's a perfect fit for the airline tubing (I'm opting to use the regular silicone and chance it becoming brittle over time--it's cheap and easy to obtain). The glass bottle has a small rubber stopper that can be made air-tight with some packaging tape (I think...), and it's small enough to suit a 2.5-gallon tank...a 2-liter bottle would've been so big comparatively.

I'm just going to throw in a hodge-podge mix of about a cup of water, half cup of sugar, and a couple teaspoons of yeast with a pinch of baking soda. That should pretty well fill the bottle. I'll probably have to reload it every few days to a week, though...being on vacation this coming week will be a good trial, since there's no fish in the tank. I'll spring for the CO2 testing strips before I bring the fish home, to make sure they're safe.

[Lady Hobbs]

Amazon Swords aren't for small tanks of 2.5 gallons anyway. These grow very large. And trying to add CO2 to a tank that small will most likely overdose the tank and kill any fish you have in there......if you have any fish in there.

Also, using 2 t. of yeast in that small a tank is gotta put out CO2 like it's nuts. I used 1 t. for 55 gallons.......back when I used it.

[dawrtw]

Ummm... I think you'd pass out. Just make a DIY CO2 system with a couple 2ltr pop bottles, some air line tubing, a one way valve, and an air stone.

Sark

Can you post a picture of this set up?

[Sarkazmo]

Can you post a picture of this set up?

Do a Google search for "DIY CO2" and you'll find a ton of different setups. They're all basically the same thing though. A vessel to hold water with sugar and yeast (sometimes a tiny bit of baking soda if your water's very soft.) The tubing directs the CO2 given off my the yeast fermentation process. The airstone connected to the air line (co2 line) helps diffuse the CO2 into the water column. That's the basics. You can do more but that's the minimum.

This mixture peters out at the two to three week mark so many use two or three bottles plumbed together so there's always a constant and pretty much regular CO2 amount being delivered to the water. The containers have to be able to withstand some pressure so 2L pop bottles are perfect candidates. Most use a bubble counter/overflow bottle as the final stage before the gas is fed into the tank. This last step catches any overflow from the yeast bottles (this can happen if the supply bottles have too much water/mixture) and also allows you to gauge how vigorously the CO2's being generated so you'll see a slowing of bubbles and know when you need to replace the mixture.

Sark

[lotus flower]

Amazon Swords aren't for small tanks of 2.5 gallons anyway. These grow very large. And trying to add CO2 to a tank that small will most likely overdose the tank and kill any fish you have in there......if you have any fish in there.
No fish in there, and my water is very, very soft...since I'm cycling, I'll give it a short try and see, since there's nothing to kill off.

Also, using 2 t. of yeast in that small a tank is gotta put out CO2 like it's nuts. I used 1 t. for 55 gallons.......back when I used it.
Thanks for that info! I guess a half pinch will do nicely. I just want a small amount of output CO2, anyway.

[Artificial]

I tried to make a DIY CO2 system in the past. It was a complete failure. Almost no CO2 was produced and it resulted in my room smelling terrible for a few weeks.

Amazon swords aren't a low light plant. What lighting do you have on the tank?