CO2 for 135 low lighplanted tank

[Wizardndog]

CO2 for 135 gal low light planted tank

I am having some difficulty finding info on co2 for a 135 gal tank. I have 195 watts of light...wanted more but cant afford the $700 plus price tags for a lighting system. So, I guess my first question is: would my tank benefit from a co2 system? I was told by my local aquarium store that it would. I am inclined to agree. My second question is: should I use a dual manifold on the regulator to disperse the co2 to opposite ends of the tank...or is there another way to use two diffusers? (Hope I have all my terminology right). Anyone have any ideas?

 

[fort384]

I think your tank would benefit from co2 addition. If you want to use 2 diffusers yo will need a manifold. Simply splitting the line can work, but it would take constant adjustment and is generally a big PITA. My recommendation though with a tank that size would be to use an inline co2 reactor with your canister filter ( assuming you have one).

 

[FishEggs]

i dont think it would benefit your tank that much to be worth the cost of a pressurized co2 system. i say save the money for the higher lighting system you want.

 

[fort384]

195 w over a 135 gal tank is not low light. The WPG rule isn't really applicable to a tank of your size. I think with co2 it could help control algae. I think you could get away with some nice medium light plants that would benifit from co2 and a modest fertilizer regiment.

 

[Wizardndog]

Thanks for the input guys. I do have two canister filters...so the in-line CO2 reactor idea is workable. Does this negate the use of diffusers? I've read statements from others that have said that using the canister filter as a dispersal method can be a problem if there is a power failure. Water can be siphoned back to the co2 unit. But I would think a simple back flow valve would solve that. Fort382, it is interesting what you say about the WPG rule. The aquarium guy that sold me the light I have, said it would be fine and he didn't try and sell me a more expense one.

 

[Blueiz]

What kind of lighting do you have, like PC, T5? I personally don't think the benifits that you would reap from having co2 with that amount of light will outway the cost of the co2 system. As someone else suggested, I would save up for higher wattage lighting, then look into adding co2.

Of course, it depends on what type of lighting you are running as well.

 

[fort384]

Rex Grigg has an article on building an inline reactor...
How To Build A CO2 Reactor | Build a Regulator | Test Kit

I don't use one of these - I use ceramic glass diffusers in the tank. However, a lot of people use similar builds and swear by them. I would think adding a checkvalve on the co2 side would eliminate any concern with back-siphoning into your co2 system.

The type of lighting (i.e. PC, T5HO) is pertinent to the discussion as blueiz said. However, I think the addition of CO2 into any planted tank, even low light tanks, has its benefits. If you are on an extremely tight budget, than it may be true that the cost for a pressurized system might be steep in comparison to the return you get. However, I still maintain that it would be worth it if you have some money to spend on the tank. For a tank of your size, the overall investment for CO2 would be a fraction of what the rest of the equipment cost. And -- if you were to save up and buy 400W of lighting, you are going to have to then add CO2 anyway if you want to use that much light. If I knew I wanted to be in the hobby and continue to upgrade my tank, I would buy the co2 first, see how it goes with your current lighting which I maintain is adequate for a low - medium tech setup, and then decide from there how much more light I wanted to add.

FWIW, I put a DIY CO2 system on a low light tank and the transformation of plants was pretty drastic. Plants that had not grown much at all started growing within a couple of days. It also helped to curb a BBA infection.

 

[marchmaxima]

I tend to agree with Fort. While you may not NEED Co2, the plants in a planted tank will benefit from it even in a lower lighting setup.

 

[timwag2001]

it's easier to prevent algae growth with co2 than it is to rid the tank of algae. so if you up your lighting and then have to save for co2, you risk algae. if you go with your co2 setup first it will be easier to subside the algae even when you decide to bump up the lighting. co2 is a nutrient. and nutrients need to be under control before you consider more lights
inline reactors are ok and yes, you want a check valve. inline reactors dissolve the co2 into the water. a lot of people argue that its better to just diffuse it. the thought is that it's hader for the plants to remove the co2 from the water than it is for a tiny bubble of co2 that sits directly the leave. i've read that the plants do better with the dissolved co2 in the first half of the day and in the later half it likes the micro bubbles under the leafs. it's a lot to read but here is some intersting read. CO2 revelations and CO2 revelations part 2#.
what i am going to try to do now is to get a manifold and split the co2 going into my tank. half into my reactor and half into a diffusor