how much carbon?

[e_baer]

I am going to make a reactor from PVC pipe, but how much carbon should I put in there and how do I know when its time to change it? I have a 90g DT, 40g fuge and a 20g sump. Thoughts?

 

[redfishbluefish]

I have a 90 DT with a 40 sump and use ca 3 cups in the reactor. I change it about every month to two months.

 

[downbeach]

If you use ROX 0.8 carbon, about 1 cup. I replace my GAC about once a month, you could do it more frequently, but after a month it's probably so coated with bacteria, that it has little to no adsorption left.

 

[dppitone]

The vast majority of folks I know change it every 30 days. I haven't read what the science is on that - how long it takes to exhaust carbon - it's probably worth looking into. I'm sure the company's that sell it have a spin.

 

[jose7878]

I run brs rox carbon. I fill my TLF 150 reactor with 1 cup of carbon and run it for 1 month before changing out the carbon as well.

 

[kschweer]

I use about 1/4 cup of rox 0.8 on my 40 gallon system. I also change it about once a month sometimes a little earlier. BRS has a nice calculator to figure out how much media to use

 

[e_baer]

Thanks for the input everyone! Another quick question....is it possible to add too much carbon? If so, what are the problems it can cause?

I am going to make a reactor from 3" PVC pipe and maybe a 1/2" pipe in the center for the water input. I will plastic weld a stand from some spare PVC pipe I have and an old powerhead will run the reactor. I will make the height of the reactor tall enough to handle the amount of carbon I will add. I will make a DIY thread when I start the project.

 

[dppitone]

If you add more than you need there aren't any negative effects.

Here's the BRS calculator. I don't know how accurate it is. http://www.bulkreefsupply.com/reef-calculator. BRS page says to replace carbon every two weeks.

 

[e_baer]

Thanks! I think now know how big to build the reactor.

 

[malulu]

if add too much, the pH will drop

edit:
http://wiki.answers.com/Q/How_does_carbon_dioxide_affect_pH

 

[downbeach]

CO2 and GAC are two different things.

 

[e_baer]

I was going to make the reactor large enough to hold about 3 cups of carbon....for future expansion of the system