I have a DIY CO2 sytem on my 10G, and frankly, it sucks. This is my fault, of course, becuase I used crappy juice bottles and such. I remember seeing a link (I think I saw it here) to plans to make DIY CO2 systems with coke bottles using bulkheads from model airplanes to eliminate using silicone to seal the lids... anyone else remeber this link or have a good system that doesn't leak? I like the idea of inexpensive bulkheads....
DIY CO2 System
- Thread starter justinb013
- Start date
I'm using 2L pop bottles, and don't use any silicone. Not sure about the bulkheads, but I read a method online, tried it, and it works quite well:
Leave the plastic disc inside the cap of the 2L pop bottle, and make the hole in the lid & cap quite a bit smaller than the diameter of the airline. Then cut the airline on a diagonal, and pull it through the bottom of the cap and out the top. It seals off nicely - so far I haven't had a leak with any of mine. Once the airline's through, cut it to about 6" and attach it to the splitter / check valve.
I do have a 3.8L juice bottle that I use, and the lid is a harder plastic and didn't seem to seal like pop lids will. I used an all purpose airplane model type glue to seal it. I didn't attach it until it had cured for days and days and no longer had any smell - as I would with silicone.
Leave the plastic disc inside the cap of the 2L pop bottle, and make the hole in the lid & cap quite a bit smaller than the diameter of the airline. Then cut the airline on a diagonal, and pull it through the bottom of the cap and out the top. It seals off nicely - so far I haven't had a leak with any of mine. Once the airline's through, cut it to about 6" and attach it to the splitter / check valve.
I do have a 3.8L juice bottle that I use, and the lid is a harder plastic and didn't seem to seal like pop lids will. I used an all purpose airplane model type glue to seal it. I didn't attach it until it had cured for days and days and no longer had any smell - as I would with silicone.
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Here's what I did for mine--
I dremeled a hole in Coke® bottle. I think the secret is to use a Coke® bottle instead of Pepsi®
Next, I cut the ends of a plastic T fitting to about a couple of mm from the center.
Put some aquarium safe silicone (purchased from Home Depot of Lowes at a much cheaper price) around the hole.
Put a small piece of plastic bag (like a 1 cm square) on top of the T and shove it through the hole. No big deal if the plastic slips through the side as long as the silicone doesn't end up in the T. If it ends up in stuck in the hole, just cut what you can away leaving anything that can't be cut.
Put small amounts of silicone around the T on the top and bottom of the cap. Let cure for a day, and it's ready for use.
The whole process minus the curing time took less than two minutes. They give a nicely sized fitting on which to stick the airline tubing.
One more thing, if your KH is low like mine, it really helps to through in a pinch of baking soda to the water.
What recipe are you using?
Sam
I dremeled a hole in Coke® bottle. I think the secret is to use a Coke® bottle instead of Pepsi®
Next, I cut the ends of a plastic T fitting to about a couple of mm from the center.
Put some aquarium safe silicone (purchased from Home Depot of Lowes at a much cheaper price) around the hole.
Put a small piece of plastic bag (like a 1 cm square) on top of the T and shove it through the hole. No big deal if the plastic slips through the side as long as the silicone doesn't end up in the T. If it ends up in stuck in the hole, just cut what you can away leaving anything that can't be cut.
Put small amounts of silicone around the T on the top and bottom of the cap. Let cure for a day, and it's ready for use.
The whole process minus the curing time took less than two minutes. They give a nicely sized fitting on which to stick the airline tubing.
One more thing, if your KH is low like mine, it really helps to through in a pinch of baking soda to the water.
What recipe are you using?
Sam
Let's see...
The "bulkheads" were much smaller, made of plastic. You could fit two into one 2L coke (that's what we call carbonated stuff in Atlanta, "coke") bottle cap, and it involved no silicone. Thanks though.
This sounds easy enough, I'll give it a shot. Thanks.
Yeah, the water here is quite soft, to say the least. I've got a little bit of crushed coral in one of my filters to help take care of that and help keep the pH from crashing, but it still stays a tad on the low side. I normally put a teaspoon or so of baking soda in every two weeks after the water change, it helps.
I am using the Nyberg recipe that DJ Len links to in the DIY CO2 sticky. It works well, and did in the past. The sucking of my system seemed to correspond to putting the exit tube in the filter intake tube as well, though I tested the bottle and found definite leakage. I re-sealed, but I'm still not getting the CO2 levels I used to with just an airstone... I think I'm gonna totally re-do the bottle with a new, 2L coke bottle. And maybe a small reactor tube, with a powerhead and sponge.
The "bulkheads" were much smaller, made of plastic. You could fit two into one 2L coke (that's what we call carbonated stuff in Atlanta, "coke") bottle cap, and it involved no silicone. Thanks though.
This sounds easy enough, I'll give it a shot. Thanks.
Yeah, the water here is quite soft, to say the least. I've got a little bit of crushed coral in one of my filters to help take care of that and help keep the pH from crashing, but it still stays a tad on the low side. I normally put a teaspoon or so of baking soda in every two weeks after the water change, it helps.
I am using the Nyberg recipe that DJ Len links to in the DIY CO2 sticky. It works well, and did in the past. The sucking of my system seemed to correspond to putting the exit tube in the filter intake tube as well, though I tested the bottle and found definite leakage. I re-sealed, but I'm still not getting the CO2 levels I used to with just an airstone... I think I'm gonna totally re-do the bottle with a new, 2L coke bottle. And maybe a small reactor tube, with a powerhead and sponge.
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Sending the CO2 into my Filstar canister didn't really work that well. I think too much of the CO2 was just being trapped in the canister. Now i have the CO2 going into the intake of a powerhead so it's chopped into tiny bubbles before it goes into the gravel vac tube.
Sam
Sam
I've had great success with either 2 liter juice bottles or soft drink bottles. I like the juice bottles because they are less prone to tipping over, since they have a larger footprint. The lids don't always seal as well though, being larger, and I'm starting to wonder if they are rated to handle any significant back pressure. I've never had one blow up (yet), but there's always the first time.
I like using those 1/4" black plastic drip irrigation fittings as hose connectors. They have a barbed tapered connection and a ring around the center that makes for a positive snap fit into a 1/4" hole. Besides, I have a million them around the garden. Drill a 1/4'' hole in the cap, leaving the inner seal in place. Coat the center lip of the connector with 90 second epoxy and snap it into the hole. Seals tight as a drum every time. In my experience, silicone doesn't stick to plastic very well. It's made for glass and tile applications. Waterproof bathroom caulk works pretty well too, but I still prefer epoxy.
For yeast recipe: ca 3/4 cup sugar, 1 tsp baking soda, 1/2 tsp yeast (for a 10 gallon set up). Dissolve the yeast in warm water first, then add to the rest. Try to get regular yeast, not the stuff for bread machines. In my hands, it lasts a couple of weeks depending on the phase of the moon.
For CO2 dissolution: I absolutely love those little powerhead rigs! I recently converted an unused powerhead into a CO2 reactor using a length of undergravel filter tube, a syringe top, and a chunk of sponge filter. About $1.50. Works like a charm in my 30 gallon. In my 10 gallon, I direct the bubbles through a rigid tube next to the intake tube of an Aquaclear 150. Slushy noise, but it works great! Still like the powerhead reactor better. I've ordered one of those little Rio pumps for $11 to make another cheapo reactor for this tank.
I like using those 1/4" black plastic drip irrigation fittings as hose connectors. They have a barbed tapered connection and a ring around the center that makes for a positive snap fit into a 1/4" hole. Besides, I have a million them around the garden. Drill a 1/4'' hole in the cap, leaving the inner seal in place. Coat the center lip of the connector with 90 second epoxy and snap it into the hole. Seals tight as a drum every time. In my experience, silicone doesn't stick to plastic very well. It's made for glass and tile applications. Waterproof bathroom caulk works pretty well too, but I still prefer epoxy.
For yeast recipe: ca 3/4 cup sugar, 1 tsp baking soda, 1/2 tsp yeast (for a 10 gallon set up). Dissolve the yeast in warm water first, then add to the rest. Try to get regular yeast, not the stuff for bread machines. In my hands, it lasts a couple of weeks depending on the phase of the moon.
For CO2 dissolution: I absolutely love those little powerhead rigs! I recently converted an unused powerhead into a CO2 reactor using a length of undergravel filter tube, a syringe top, and a chunk of sponge filter. About $1.50. Works like a charm in my 30 gallon. In my 10 gallon, I direct the bubbles through a rigid tube next to the intake tube of an Aquaclear 150. Slushy noise, but it works great! Still like the powerhead reactor better. I've ordered one of those little Rio pumps for $11 to make another cheapo reactor for this tank.
whats the big deal with using silicone? it takes 2 hours for it to harden and costs like 2$ for a tube...do it once and your set...
for a 2L bottle I use this recipe:
1 cup sugar dissolved into 6 cups very hot water
cool the mixture to room temp
1 tsp yeast (fleishmans)
no mixing/no stirring
for a 2L bottle I use this recipe:
1 cup sugar dissolved into 6 cups very hot water
cool the mixture to room temp
1 tsp yeast (fleishmans)
no mixing/no stirring
maybe it was this article
you can see the small bulkheads here
http://www.qsl.net/w2wdx/aquaria/diyco2.html#6
you can see the small bulkheads here
http://www.qsl.net/w2wdx/aquaria/diyco2.html#6
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I've used silicone and hot glue, neither stuck to the cap or tubing very well. I've had moderate success with PL Premium if I add enough of the junk to cover the full top of the cap. The last bottle that I made I drilled the hole out with a bit about 1/8" smaller than the airline tubing. I also used the PL Premium, but it didn't stick to the cap, but there still weren't any leaks, the tubing sealed to the cap quite well on its own, so why bother with other sealants? Although the model glue is intriguing...