New to CO2...

[ngo911]

I just set up a 2L DIY CO2 for my 29 gallon, medium planted, 65W PC tank.

The mixture I used was 2 cups of sugar, 1/2 tsp of yeast, and 1 tsp of baking soda.

The bubble rate is 67 bpm(bubbles per minute) and the output is connected to the intake of my AC50 filter.

The problem is that my drop checker is still blue after 5+ hours, meaning I don't have optimum co2 levels. Using the pH/kH relationship of my tank water (7.0 pH and 4 dkH), I have about 12 ppm.

How can I improve my co2 levels without adding another bottle?

[eternity302]

Maybe try metricide? but if anyone got any knowledge, please share =)

[Captured Moments]

AC50 filter is a Hang-on filter and these types of filters are not recommended for planted tanks because of the way the water is returned back to the tank. the water cascades down and consequently quite a bit of turbulence and surface churning of the water. As a result, a substantial amount of the dissolved Co2 that you have managed to inject into the water via the intake of the filter will for the most part "evaporate" to the air.
Co2 is a gas that exchanges quite freely between the medium of air and liquid depending on the higher concentration at the source flowing to the point of lower concentration at the destination point. Since air is usually around 5 ppm of Co2 concentation and since you are trying to target a concentration of around 25 ppm of Co2 in your tank water, it is easy to see that Co2 is constantly being discharged into the atmosphere and thus the need to continuously pump Co2. By having turbulence at the surface, you are accelerating that Co2 loss and depending on the output capacity of your DIY Co2, you may never be able to reach your targeted Co2 level.
I am not saying you cannot use a HOB filter but it just doesn't help your cause unless you inject more Co2 at a faster rate to compensate of course. This may prove difficult on a DIY Co2 system. I find the Co2 output on DIY Co2 limited and inconsistent. You may get decent output for a few days but it tends to drop off after a while. A lot of people have tried various variations on the recipe (even with jello, and different kinds of yeast) to try to improve on Co2 production and most of all to try to extend the Co2 output over a longer period.
I think canister filters are better than HOB filter for planted tanks on the aspect that the return on canisters is via a spray bar and people usually submerge the spray bar or what have you under the surface so there is practically very little surface turbulence, thus reducing Co2 loss.
What kind of plants do you have in the tank?
65W of PC light is quite a lot on a 29 gallon and coupled with the fact that it is only medium planted, and the most important of all the Co2 level not being at a sufficient level, will quite likely create algae problems.
At any given level of light, you must provide sufficient Co2 or the plants will not be "very happy". The more light, the more Co2 you must provide.
You can't really use the KH/PH relationship table on your tank by measuring the PH and knowing the KH in the water of your tank, and figuring out the Co2 ppm level. In practical, it doesn't work because there are other factors that will throw the figures right out. There are things in the water that affect the PH aside from the Carbonate hardness alone. You have driftwood that lowers the PH, you have fish "poop" and waste, and maybe buffers and boosters that you may add to the water.
You can consider supplementing your Co2 with Flourish Excel or Metricide if you want. Quite a lot of people here use it.

[ngo911]

I took half of a water bottle and placed it underneath the output of the filter to disperrse the flow. Would this increase or decrease the rate I'm losing co2?

It looks like I will need to try a different method of diffusion. Metricide will be my next option, but I've heard that Excel melts vals. Does Metricide do the same?

Most of the plants are low light plants. So far, I haven't been having any algae issues. More plants will be added in the next month.

Thanks for the replies.

[neven]

generally when people say excel or metricide, they are considered the same, benefit wise to the avg hobbyist. Yes it does melt vals aswell.

As for hang on back's, you can get them to work if you raise the water level up high enough to avoid surface agitation from its water fall. This helps lower the degassing aspect Hang on backs have, but doesn't solve the co2 loss from dissolving the co2 into the AC50. With spending minimal money, you could get something like the hagen mini elite internal filter, it goes in the tank, you can hide it easily behind decor (or plants) and it comes with a venturi connection.

If you dont like the misting, or dont want to spend the $12 for mini, then you'll need to stick with the co2 in the intake. as i said, water as high as possible.

You'll be told plenty that DiY doesn't work well, and its high maintenance, but a little research and you'll learn how to work with the yeast so it thrives and lives rather then kill itself off from too high alcohol quickly. Your current mix you use would be one that kills yeast off prematurely, the 'high maintenence' kind, so if you wish to continue making your own, theres plenty of articles on jello, or even a protein fortified mix.

Also if you wish to leave your mix the way it is, you could half your yeast amount, and add a second 2L bottle and replace 1 every week so they're offset. Its really a must for your kind of co2, it'll lesson the dips your tank suffers when the mix is about to die out (week and a half in most cases). Make sure you use wine/champagne yeast rather than bakers, it'll outlive the bakers.

My point is there's plenty of solutions, not simply Buy a bottled co2 system as many will tell you. Metricide/excel is definately an option unless you have vals, Riccia (if you dose high), Anacharis, Pellia, liverworts, and probably a few others.

[ngo911]

Great info, thanks neven.

I think I will be getting an internal filter as you suggested because I need better flow near the surface of my tank anyways. Two birds with one stone .

I do have vals so I guess metricide isn't an option atm. I'll look more into other recipes and two bottle systems.

[effox]

Use champagne yeast.

Just be careful of the amount, I used a tablespoon instead of a teaspoon when I was drinking and I gassed 1/3 of my fish with 3 bps in my 29g biocube.

[neven]

yea i too almost killed my fish when i switched to champagne + jello mix, had move the spray bar towards the surface. Keep an eye on that drop checker every time you put new mix in, or try somehting new, check it often.

[Captured Moments]

If you are just starting out with plants, it makes sense to start off with DIY Co2. It's cheap enough and will give hands-on experience with dealing with Co2 and the rest of the setup such as lights and ferts. When I started off with DIY Co2, I found it kind of neat to prepare the mix and see Co2 bubbles come out of a tube. Call me a geek if you like. But after a few months, I got tired of preparing the mix every 2-3 weeks and sometimes I would have issues with not enough Co2. By that time I was already into 3 tanks all requiring Co2 so I decided to spend some money and go to pressurized Co2. I like it now and I don't think I will go back to the yeast method unless maybe for fun again on one tank. There are advantages to going with pressurized especially if you are moving into high light situation where the Co2 demand is higher and a requirement to maintain stable Co2 level.
On a larger tank, it becomes increasingly difficult to achieve desired Co2 level with the yeast method unless you go with a dual or triple 2L bottle setup...

As Neven said earlier, Flourish Excel or Metricide are a liquid carbon solution and can be used instead of Co2 but certain plants don't like it. It's worth mentioning that plants in general will grow much faster under Co2 than under Excel or Met., all other factors being equal, and I read somewhere that under high light, Excel or Metricide can become lacking in a sense that the plants are not able to assimilate fast enough the carbon?

[ngo911]

Thanks for the tips.

The tank is in my room so I can check the drop checker often.

If I ever get a larger tank, I would probably go pressurized. But as you said, I am just starting out with my first planted tank and just trying to get some experience with DIY co2. Hard not to try when it only cost 5 bucks in materials!

Unfortunately, King Ed's was out of stock of the Elite Mini filter so I still didn't try that as a reactor. The search continues...