Co2 issue

[Yellow Eye Tang]

I've made a DIY Co2 using a 2 liter and so far all the set up seems to be working but my plants are not taking off like I would expect. It's been running for about a month and I change the Co2 mixture every week. I've noticed pictures of others 2 liters with lots of "foam" bubbles in the top. Mine seems always flat on the top but it does have very small bubbles churning on the surface. I've been treating with florish excel and I'm noticeing an algae growth. It's not out of control but it is there. Can anyone think of what I might be doing wrong? Also.... the powerhead is sitting on the top of the tank... should I move it to the bottom near the gravel???

 

[kangster]

up the amount of yeast and sugar in the mixture

 

[timwag2001]

ok.. lighting (wpg)? ferts?
my diy bottles are only foamy when they're brand new. they look like bottles of crap the next day. did you set up a bubble counter with it? can you tell if there is co2 going into the tank?
flourish excel is just another source of carbon and doesnt have any of the macro or micro nutrients needed by your plants.
your powerhead is at the top of the tank... is the flow of water breaking the surface of the water? is there any surface agitaion? bubble strips?

 

[Yellow Eye Tang]

Yes there is a regular HOB filter and as water evaporates it does cause surface agitation. I do not have a bubble counter with it. It basically is running straight from the 2 liter through a check valve and into a powerhead that allows an air tube to be plugged into the top. It seems to do a great job breaking up the bubbles and distributing the C02. It's a 20g tank with a 65w current usa fixture on it, allthough the bulb is half actinic and half 10,000k. I DO have another 15w sunlight bulb I could put on if needed but i'm thinking I just need to get a full 10,000k bulb for my fixture. Do I need to set the powerhead that is running the C02 at the bottom of the tank?

 

[timwag2001]

surface agitation allows for the co2 in the water to leave the tank. so try to limit it.
you can make a diy bubble counter which also serves as a filter to catch and yeast crap that leaves your bottle with a small soda bottle like this http://fish.cecolts.com/pics/c15.JPG.
you have over 3 wpg. prob a little excessive. try cutting back to around 2 wpg for about 8 hours a day and you prob won't have as much of an algae issue.
i dont think that the placement of your powerhead is overly important but i would think that if its lower in the tank it would give more time for co2 bubble rising to the surface to dissolve into the water some more. look up rex griggs diy reactor. i made a similar one and i don't even see bubbles come out. all co2 just about completley dissolved

 

[Rikesh]

There's a trade-off between sugar and yeast. more yeast will produce more bubbles but the mixture will die quickly. less yeast and your mixture will bubble less but will go for a longer time. The "bubbling" also depends on room temperature(yeast's metabolism)

 

[TheNamelessPoet]

I shake mine a little 2 times a day. I have the exact same setup Yellow... 20 gallon 65 watts. I use ferts I bought from another forum member and shake my bottle at 8 when th elight kicks on (just a little so it fizzes for about a minute...) then again at 6 when I get home from work so it fizzes (the difuser) about 5 minutes... I get about 1"-1.5" on the day I fertalize and sometimes the day after... then on the other days I get about 3/4" ro 1". I fert 2X a week monday and thursday and do my water changes on thursdays (every other if the nitrates are below 25)

I go with about 20-35 ppm with my nitrates... I dose that it drops below 25 usualy. The nitragen I THINK are what the roots grow (been a while since I went to school so I dont remember exactly)

 

[timwag2001]

I shake mine a little 2 times a day.

my dad always told me that if you shake it more than once, you're just playing with it.

imo if you feel like you have to shake you're bottle to get more co2 out, you should add another bottle. i dont like to shake it because when you do it expells a lot of co2 quickly and then dies out and takes a while to repressurize and put out more co2. i would also bet that it shortens the life of the bottle. i know that my beer goes flat after i shake it.

i would add 1 bottle a week untill you get to your desired co2 levels and then once you get there, switch out the old bottle once a week.