a few questions about carbon


New member
I have been using BRS ROX carbon for a few months and have been happy with it. I recently bought some Black diamond thinking it would be ok based off of an atricle I had read a few weeks ago. I have not used any of the BD yet. I read a thread tonight about people steering away from BD due to the lower quality. I hate to purchase the ROX due to the $35 shipping and having to spend $175 on stuff I dont really need to get free shipping. So I was looking for opinions. I read that Two Little Fishies is a pretty good GAC. This is easily accessible for me. what do you think?

Also, I have a 75 gallon tank with mostly soft corals; leathers, zoas, tree coral, along with some LPS. How often should i be running my carbon? Is it more a personal choice? I have been running it 24/7 changing it every three weeks.

Thanks in advance


New member
I've used the TLF stuff and would recommend it. It has also been acid washed to remove ash, aka no phosphates. I've never personally used brs rox, so I couldn't directly compare. It does however seem pretty close to the brs lignite (which I currently use) in appearance.


New member
ROX 0.8 is probably the gold standard for GAC, and preferred reefer pricing at BRS is the best I've seen. I'm using individual BRS reactors for both GAC and GFO. My system calls for about 1 1/2 cups of each. I have a MJ400 in a reverse flow connection on the GAC, and a MJ600 on the GFO connected normally. Contact time is important for both media's, but the GFO needs to be kept fluidized so it doesn't clump. I average about 9 to 10 weeks in my system using the HC GFO, and replace the GAC once a month, both are run 24/7.
Do you know of some local reefers who might need to buy some supplies? If so, you might get together and do a quasi group buy to get to the minimum order for free shipping.


Cheesehead Reefer
Sometime within the last year I read about a carbon being recalled due to heavy metal contamination from the manufacturer.

I think it might have been Black Diamond. Definitely do some more research before you put the BD into service.


New member
I'd also check the BD for phosphate. I only use the ROX now.

I usually make big orders all at once from BRS to get the free shipping. I'll order carbon, gfo, esv 2 part, and ro/di filters all at once.


Go Spurs Go!!!
Premium Member
Why are you paying $35 for shipping?

Kent carbon had the contamination.

I have used Rox .08 for years and won't use anything else.