Any GAC experts in the house?

[Doctorgori]

Pretty sure this is a re-tread but can someone post a link or primer on GAC: the main types, differences and advantages.

I trust the BRS crew more than less, but still can wrap my head around the cost and justification of the ROX type carbon...

Also wondering how quickly it is really depleted in SW tank and which type of carbon gives you the most bang for the buck filtering saltwater (they say ROX is the most efficient but its VERY expensive)
Basically why does a $7 10” block of carbon for a RO system last for 100 of gallons in tap water yet $30 worth of ROX is depleted in a SW tank in hours/days?
...would a RO type carbon filter work in SW?

 

[Ron Reefman]

I've been keeping reef tanks for 20 years and in all that time I used GAC for maybe a year. I have a big bottle that sits on the shelf in my reef room and a reactor for it as well. But unless I have some issue in the tank that requires it, I don't use it. To me, it's a crutch.

 

[Doctorgori]

I've been keeping reef tanks for 20 years and in all that time I used GAC for maybe a year. I have a big bottle that sits on the shelf in my reef room and a reactor for it as well. But unless I have some issue in the tank that requires it, I don't use it. To me, it's a crutch.

Its mostly for yellowing and I’m trying to figure out the most cost effective way to deal with it ....
wish I knew the pros & cons vs regenerative media like Purigen

 

[lakai]

The carbon blocks in your rodi is compressed with a binder that makes it good for high pressure , low flow. They are not made to filter out organic compounds like we see inside our tanks. You could do it but quickly find that it will clog up very quickly.

 

[Doctorgori]

The carbon blocks in your rodi is compressed with a binder that makes it good for high pressure , low flow. They are not made to filter out organic compounds like we see inside our tanks. You could do it but quickly find that it will clog up very quickly.

Appreciate that ... simple, easy and understood.... I’m not being “search lazy” ... I did do a search on Purigen, Carbon et here on R2R.. like this
.. A lot to go through and I’m still reading ....

 

[X-37B]

I run Rox 0.8 in my 120.
I use an aquamax reactor that holds about 1.25 cups with floss and pads that keep it inplace.
I use Rox because its clean and I dont even rinse it.
Plus you do not need as much as you would with a lower grade of carbon.
I run it 24/7.
I believe it helps remove the stuff I cant see or test for.
I buy the 3lb jar for $53 at lfs and it last around 9 months.
Less now that I run it on my 45 frag system too.
I change it every 3-4 weeks.
It runs about $5 a month for my 120.
Cheap insurance and it keeps the water crystal clear.
I dont think you need to run as much as many people do.
The BRS calculator says to use 3/4 cup for my 120 so I run about a half a cup more because I do not do scheduled water changes.

 

[homer1475]

ROX is worth the price if you consider how much dust the cheaper versions have. And carbon dust has been shown to cause HLLE in certain species of fish.

I have always run carbon 24/7/365 in every tank I have ever owned Salt or FW. It just makes the water crystal clear, as opposed to a slightly yellow tint salt water tanks typically have.

 

[Doctorgori]

Thanks for the above replies. I truly already know a LOT of these topics have been beaten to pulp on these forums and I was expecting more yawns than replies...
But with 600 g’s worth of SW tanks ROX gets dang expensive 24/7 so I went to rechargeable Purigen but I’m not convinced its a true carbon replacement, AND BIG THUMBS to mentioning dusty wasteful cheapo carbons!!!
THEN Melev, BRS and a few other reliable sources mentioned running carbon past a few days may have a point of diminishing returns.

So now I’m here looking for input. ...

 

[GlassMunky]

THEN Melev, BRS and a few other reliable sources mentioned running carbon past a few days may have a point of diminishing returns.

So now I’m here looking for input. ...

Diminished returns in what sense?
That over time it will release the organic snack into the tank?

 

[X-37B]

Thanks for the above replies. I truly already know a LOT of these topics have been beaten to pulp on these forums and I was expecting more yawns than replies...
But with 600 g’s worth of SW tanks ROX gets dang expensive 24/7 so I went to rechargeable Purigen but I’m not convinced its a true carbon replacement, AND BIG THUMBS to mentioning dusty wasteful cheapo carbons!!!
THEN Melev, BRS and a few other reliable sources mentioned running carbon past a few days may have a point of diminishing returns.

So now I’m here looking for input. ...

1. The key their is, may have a point of diminishing returns.
May meaning I am just guessing.

 

[Doctorgori]

Diminished returns in what sense?
That over time it will release the organic snack into the tank?

I’m thinking the gist of it was it gets depleted within days ,,, I figured it didn’t last months but days? I was not aware