DIY CO2 Diffuser

[azn_fishy55]

I just test drived my Pump Diffuser in the pool and the water was siphoned into the airline tubing so it was a failure. I have heard alot about the diffuser in the attachment. How do you make it?

[dskidmore]

Are you doing yeast generated CO2 or compressed CO2 canisters? I just use a fine pore airstone for my CO2 diffuser, but when you're generating you can afford to loose the extra gas.

[sudz]

I stick mine in my powerhead. Its got a feed for it. the only thing that bugs me slightly is that it seems to make a mild vacume in the pop bottle. Anyone else have this problem?

[azn_fishy55]

I have yeast generator DIY CO2 system

[dskidmore]

Originally Posted by sudz

I stick mine in my powerhead. Its got a feed for it. the only thing that bugs me slightly is that it seems to make a mild vacume in the pop bottle. Anyone else have this problem?

Those powerhead inputs are designed to pump air into the water, not passivly take pressureized input. You're bount to have a vaccum situation with that method. You could use a T and a check valve to let in some regular air when the airline pressure is too low.

[czcz]

azn_fishy55, search for gravel vac powered reactors.

sudz, as long as the mix is producing gas you are okay. I use venturii method with slightly different details too, and with regular bottle changes have not had issues, fwiw.

[sudz]

I wasnt sure how much vacume it would actually create, so i left a bottle full of dechlorinated tap water for a while, instead of yeast, just incase it collapsed the bottle and sucked up water. It didn't... just in case, i just have a brass... nobby thing that gradually turns on airflow. I turned it off, and let some pressure build up, then just wiggled the thing on a tiny bit, and now air kinda leaks out. keeping the bottle mildly pressurized.

I THINK it should be ok.

however, what are the concequences of running CO2 when you don't have proper lighting?

[malkore]

Couple things here:

1. if you're gonna create a vaccum with a DIY setup, use very thick plastic, or glass, juice bottles. a vaccuum will collapse the pop bottle eventually. the risk is always there.

2. never EVER restrict the flow of a DIY setup from venting the CO2 it creates. I can adn WILL explode when the pressure builds up. I can't tell if the brass valve is being used to restrict the DIY, but if it is, remove it. Again, the risk will always be there for it to literally explode if you cap the pressure.

3. to answer your question, running extra CO2 when you don't need it is just a waste of time and effort. DIY rarely hits lethal CO2 levels, so you'd basically have plenty of CO2 in the water, which may benefit the plants a little, and will definitely lower your pH.

[sudz]

alrighty. The reason why i have it in already is i want to get it ready for the influx of plants it'll be reciving the second i get my 96 watt PC setup (hopefully this friday!) The PH is at 7.2 atm. I'll be adding a second bottle once the lights come. the main reason for the brass valve is to turn off airflow so when i disconnect the bottle water doesn't come pouring down. As an afterthought this wouldn't happen because the powerhead sucks air through the tube. *doh* so it would never pour out the tube when i disconnect the bottle, it'd just inject a lot of air into my tank instead. :|

*can't wait until lighting system comes in!*

[malkore]

sounds like you have the plan laid out. ramping up CO2 levels in preparation for the lighting isn't a bad idea. I'd have the second bottle prepared for the day the light gets put on. Its not like you'll instantly get algae with the new light and not enough CO2, but keeping them full of carbon from the beginning is best, as it'll reduce stress from the 'environmental' changes you're introducing by the lighting upgrade.

DEFINITELY keep an eye on your nutrient levels after adding the lighting. nitrates are probably the most likely to bottom out quickly.

[Zezmo]

If you add a DIY bubblecounter/gas separator and put that in a stiff plastic bottle it will reduce or eliminate the possibility of collapsing your yeast and sucking stuff into your tank.

In case you do manage to get excess CO2 (causing a PH crash), then having an air pump and air stone handy to force the CO2 out of the water could be handy.

[hashbaz]

I thought of putting a on/off valve at each generator, (to prevent CO2 loss when changing 2L bottles) but decided not too. I don't want to risk forgetting to "open" one and blowing up a 2L bottle! Keep it simple.

[ringfinger]

Hey azn_fishy55,
I'm not sure if you are still trying to make your own diffuser, but this might be a good chance to buy one. The site, http://www.plantguild.com/ , is selling the power reactor you had a picture of for $32.50 plus about $5 shipping. Just click on the "specials" button to find it. Very reasonable if you have the spare cash. It looks like these models have a small crack in the cylinder which has been solvent welded. They would work perfectly, and cost less than the $50 original price.

[azn_fishy55]

well 32.50...37.50 is alot of money spending on a diffuser. I could make one my self for at least half the price!