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CO2 for Cheap

2189 Views 16 Replies 11 Participants Last post by  OverStocked
Hi, I wanted to ask if anyone knows of a way to measure CO2 in the aquarium in a very cheap manner? I'm looking for something custom built or store bought for around $10. I currently have a 60 gallon with just 4 live dwarf lillies that are getting big. I plan to add about 6 aponogetons and up to 4 additional dwarf lillies and I want to be sure I will not need C02 injection as I am really trying to avoid it - due to cost and upkeep requirements. I simply want to know my current levels and that the additional plants will not require the addition of a CO2 system. I'm new to plants and I do not want a planted aquarium - just lower nitrates. So, I'm guessing if the plants lack CO2 they will begin to die off or discolor or something like that?
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At $10, you're talking about Excel, which is a liquid carbon source, or a DIY system that involves a couple plastic bottles, sugar, water, yeast, some tubing, and a cheap diffuser ($5 maybe from Evilbay).

Excel is made by Seachem, and is just glutaraldehyde, extremely diluted by water.

If you wanted a decent, safe pressurized system, it's gonna be $125 absolute minimum for cheapo regulator, paintball cylinder, and fittings.
DIY yeast activated CO2 is one way but not cost affective in a 60g tank. You would probably need 2 to 3 2L bottles to provide enough CO2 for a 60g tank. The yeast would lose their effectiveness in a week or 2 and you have to remake them again. How much a 5lb sugar would cost? $3 to $4? You would need about 2lb of sugar for each 2l bottle. You can do the math. In a month, you would be spending something like $20 just for the sugar alone.
Are you asking for a cheap way to add CO2, or a cheap way to measure it?

It sounds to me like you want to measure it. Since it sounds like you don't have CO2, you levels are going to be pretty low. Not anywhere even almost near a DIY or pressurized system.

Not all plants require CO2 injection, but those that do will slowly die off without it.
If your lighting is just right you won't need CO2. Check out the Low Tech forum for lots of info on this. The sticky at the top of the lighting forum has some threads that should help you know if your lighting is low or medium or high.

If your lighting is high enough that the amount of CO2 in your tank is insufficient for the plants then algae generally will start to become a nuisance. If your lighting is seriously too low then plants won't grow well.

If you have 6 aponogetons and 8 lilies then your tank will definitely look planted soon. Those are beautiful large growing plants.
Keep the tank low tech and a rich substrate, well fertilized. Most plant will grow slowly.
Hi, I wanted to ask if anyone knows of a way to measure CO2 in the aquarium in a very cheap manner?
There is no-way to measure co2 in the aquarium in whatever manner..by growth of weeds you can tell if tank has enough co2 or an algae indicates low level of co2. But there ain't exact measurement that proves otherwise.

Now if you want cheap source of co2 DIY yeast method or dose glutaraldehyde(Metricide). Do further forum search, spend 30$ and it will last for years if you have smaller tank..
There is no-way to measure co2 in the aquarium in whatever manner..
A drop checker will give you a ball park measurement. There are CO2 sensors that'll work pretty accurately but they cost thousands of dollars.
Sorry, I misread. I translated "measure" as "inject".

You can get a drop checker and 4dkh solution for a bit over $10 from Evilbay, but that won't do you any good if you're not adding any CO2 - it will always be blue.

Basically, as long as you keep up surface agitation, there's no way plants will lack for CO2 under low light. Under higher light, there are a number of nutrients, including carbon, that could be limiting factors.

So, if you're planning on adding plants with the lights you have now - assuming your plants are doing fine, as you say - all you need to do is make sure you have surface agitation. Additional fish won't hurt, as they (well, their poop, really) will supply some extra nutrients.
You probably won't have enough to measure. Either way, it'll be negligible. But if you do decide you want to use co2, this should help you out. http://www.plantedtank.net/forums/showthread.php?t=132696

You can get/make the liquid inside (4dhk- baking soda- solution mixed with Bromo blue aka pH reagent) easily as well.
If your not looking to have a planted tank. Maybe just get a water hyancinth and let it float.or a pot of pathos ivy from the grocery store or hone depot and set the pot next to the tank and drop a leaf in. Pathos doesn't need any more light than your house has. And might look nice on top of something next to your tank or siting on top of it.
Hi again,

I appreciate all the responses. For now I am just trying to see my CO2 levels and do what I can to prevent the need to setup an injection system. I found a cheap CO2 indicator online for $6. So, I will use that to monitor my levels and hopefully that will clear up my CO2 situation (i.e. that the CO2 level would be 'ok' to support more plants). Currently, there is only a 3,100K 15watt light that sits over where the current plants live and they are growing pretty well. I guess this is classified as low-medium light. In the future I may add a 5,500K bulb in my other light fixture. I don't understand the comments about the light and CO2 relationship. I should also note that I have about 200+ guppies in the tank and they are having babies daily. I assume that alone puts my CO2 levels high, but I'll know my CO2 levels more accurately once I have the indicator setup. Futhermore, there's tons of surface agitation as I am running multiple filters - totalling somewhere around the 700GPH level.
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The co2 indicator wont' show anything though because if you are not ADDING them, they are at or below atmospheric levels.

If you aren't adding co2, using an "indicator" or drop checker is literally throwing money away. There isn't any point.

The way you'd know if you needed to add more co2 would be poor growth, algae taking over, etc.

Your fish are not putting your co2 levels anywhere near "high". I promise. What you have is low light, low tech. Your plants are undemanding. If your fish really were putting much co2 into the tank, all of the surface agitation you're providing would degass it. You're tank in reality runs at lower co2 than atmosphere.



1 x 15 watt bulb would put you at low to very low light.

When you get your drop checker, you're going to find that it says you have basically no co2. If it says you have any more than that, it is wrong.

In a non co2 injected tank, drop checkers(indicator as you're calling it) are pointless. Use the plants to tell you if they need more.
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A drop checker will give you a ball park measurement. There are CO2 sensors that'll work pretty accurately but they cost thousands of dollars.
An oxyguard portable meter is a good place to start for a few thousand

A hach titration kit is basically an instantly usuable drop checker. Its a titration kit that relies on ph change by carbonic acid to determine co2 levels its a little more accurate than a dc and has varying ranges for such
Hi again,

I appreciate all the responses. For now I am just trying to see my CO2 levels and do what I can to prevent the need to setup an injection system. I found a cheap CO2 indicator online for $6. So, I will use that to monitor my levels and hopefully that will clear up my CO2 situation (i.e. that the CO2 level would be 'ok' to support more plants). Currently, there is only a 3,100K 15watt light that sits over where the current plants live and they are growing pretty well. I guess this is classified as low-medium light. In the future I may add a 5,500K bulb in my other light fixture. I don't understand the comments about the light and CO2 relationship. I should also note that I have about 200+ guppies in the tank and they are having babies daily. I assume that alone puts my CO2 levels high, but I'll know my CO2 levels more accurately once I have the indicator setup. Futhermore, there's tons of surface agitation as I am running multiple filters - totalling somewhere around the 700GPH level.

Listen, what may kill your guppies could be the excessive organic load, not the CO2 concentration. I have been keeping fish more than 10 years. An air stone is generally sufficient enough to oxygenate your water. If you are not adding any CO2, your CO2 level would never high enough to be registered by any measure tools. No, the CO2 from your fish would never be enough to grow your plants.
Well, the results are in. My indicator ranges from yellow to green to blue. My current status is "blue," which the notes seem to indicate that the CO2 level is low or insufficient. Apparently, green is the color of normal or good CO2 levels for plants. Now, this presents a worry - why are my current water lillies growing? I'm guessing I really shouldn't be adding more plants (specifically the aponogetons and additional dwarf lillies). I really don't know much about plant biology - I just know that plants use CO2 and I don't know how much a plant actually uses or needs in a day.
Lillie's are on the surface. They get their carbon from the air.

You can have plants in a low co2 tank. Just slow growing undemanding ones. However, your light isn't enough to sustain much at all.

I really think you're misunderstanding this whole light/carbon/nutrient balance.

In low tech tanks people densely plant them all of the time with no added carbon dioxide. It is just a matter of choosing slower growing plants, with low light. A nutrient rich substrate can help make it even easier(soil, aquasoil, root tabs, etc).

However, your light is VERY low. So much so, that at the bottom of the tank it is practically doing nothing.
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