Gfo and carbon dosing

[Proteus]

Read a artical that suggested that running gfo and dosing carbon may be counteractive.

Was wondering if anyone does both. And what there views are

Discuss. Lol

[eli@fijireefrock.com]

i run both on a mixed tank as a series.
Run carbon and HCGFO 24/7 with low flow and never had any issues on SPS LPS or my soft corals.
Usually change the carbon every 5 weeks and I see better extension on all my corals. Never had any problems with hair algae or any type of plant (although I like to see some green but never grows ) I run HCGFO as extra on my RODI water feeding my reef tanks.
All in all I think they both do better my tanks than not.Both media have different removal qualities as I don't see to be counteractive.Could you post the link to the article you read

[ScubaSteve]

In my opinion, carbon dosing does a much better job at removing nitrates than phosphates (based on both experience and the science behind it). I use a phosphate remover (Foz Down) or Rowaphos in a TLF reactor in parallel with VSV dosing.

[Proteus]

http://reefkeeping.com/issues/2008-08/nftt/index.php

Above is the artical I had read.

I have started running gfo a month ago and have been dosing 2 weeks now at a current level of 2ml a day in a 240g system.

[ScubaSteve]

Yes, I've read that article too.. but I kinda disagree with his comments on GFO being unnecessary.

Bacterial removal of nutrients is no new thing; it's actually fairly common practice in water treatment (one of my fields of research). The thing is, if you break down the chemical equation for nutrient conversion to biomass (how much mass of nutrient becomes mass of bacteria), phosphates are removed much slower rate than nitrates (at least for the bacteria we commonly see in our tanks). So your bacteria driven system will most likely be carbon and nitrate limited rather than phosphate limited, meaning you will have an excess of phosphates (though your phospahte level WIL go down); it helps to have GFO or something similar to handle the rest.

That being said, if your have a TON of GFO and are removing phosphates very aggressively, you will make the bacteria driven system phosphate limited and it does become counter productive. This situation is not as likely as the first.

[George]

In theory, GFO can absorb all of phosphate in your tank eventually (if you change your GFO frequently). At the same time, the bacterial triggered by carbon dosing also needs both nitrate and phosphate with some ratio (some say 16:1, but I think different strains of bacterial take those 2 in different ratio. Anyhow they always take more NO3 than PO4). If you tank is running out of PO4, carbon dosing won't do you any good.

[Proteus]

Lol. I have no shortage of phosphates

I ask as I stupidly overfed my tank. My wife was feeding while I was at work and I was feeding in evening. Not knowing that she was doing so. Or that she was doing so twice a day. I was feeding in evening. Since I have a shy Cbb which doesn't care for Mh lights so I fed when just t5 were on. I first notice when I spotted HA. and had a stag loose a little flesh. Then with a spike in po4 I changed gfo and decided to try carbon dosing. I also have a refuge with mangroves and Cheto. Though Cheto doesnt want to grow