- BRS Bulk GFO Granular Ferric Oxide - High Capacity
Why does BRS recommend this?
Phosphates are going to be one of the biggest battles we have with a reef aquarium. The BRS GFO works even better in reactors due to it being denser than most other GFO. The price is just about double of standard GFO however you only need to use half as much which equals out in the long run. High Capacity is going to have less dust than almost all other GFO on the market and being able to buy it in bulk saves a ton of money.
High Capacity GFO is the best performing GFO we stock and capable of removing close to twice the phosphate as standard GFO by volume. We recommend this when you have a large tank or limited room in your media reactor.
Granular Ferric Oxide (GFO) removes phosphate from the aquarium and is one of the most commonly used filtration media used in the aquarium industry. GFO is one of the few ways to easily maintain ultra low phosphate levels on a consistent basis. Maintaining these ultra low levels will help prevent algae outbreaks as well as treat existing algae issues. Your aquarium's glass will also stay clear and free of the green hue significantly longer. GFO is most commonly used in a media reactor like the BRS reactor or media bag.
Phosphate inhibits proper coral growth by incorporating itself into the corals skeletal structure which makes it difficult for the coral to grow by laying down additional calcium and carbonate (alkalinity) ions. Maintaining ultra low phosphate levels will increase the growth of any SPS or LPS coral.
Algae outbreaks are one of the most common reasons for a complete tank shut down. We recommend preventing them by maintaining an ultra-low nutrient level environment where it would be difficult for them to get out of control to begin with. It is much easier to prevent outbreaks than it is to treat existing outbreaks.
Two Types of GFO:
- Granular GFO is varied in its shapes and requires the least amount of flow to tumble. Good for reactors.
- High Capacity GFO is twice as dense as Granular GFO, so twice as much material will fit into a reactor. It's extremely hard and has less dust to begin with. Fewer fines will be created during use and transportation. By volume, High Capacity GFO will remove roughly twice the phosphate compared to the same volume of Granular GFO. Best overall performance.
Special note on fighting existing algae problems: Algae needs three main nutrients to grow: phosphate, nitrate and light. Reducing any one of these will significantly slow down algae growth but may not completely solve your issue. Once algae takes hold, it can be a difficult battle but it is winnable. The best offense against algae is to take preventative measures and attack nutrient before an outbreak is apparent. Use the following suggestions and be aggressive if an algae problem is already present:
- Maintain undetectable phosphate levels with good feeding habits and use a phosphate remover like GFO. 99% of all phosphate is added to the tank via foods.
- Control nitrate levels by reducing feedings, increasing the water change schedule and maintaining a properly sized protein skimmer.
- Use nutrient free RO/DI water for water changes and top off water
- Shorten your lighting period or intensity. In some cases aquarists have found replacing old bulbs that have fallen out of their intended spectrum helps as well.
- Continuously remove as much algae as possible by hand.
- Add predators - nothing helps an algae outbreak as much as critters who eat it all day long. Various tangs, lawn mower blennies, crabs and snails are all good options. It is also theorized that a healthy pod population will also control algae growth before it gets a chance to take root.
Note: All Bulk GFO is packaged by volume.
Expensive but it works By xjv152 on 4/2/2018xjv152 would recommend this product to a friendRinses clean, does the job as stated. Price is HIGH CAPACITY as well
Works! By Tom on 3/9/2018Tom would recommend this product to a friendI switched to the high capacity a couple of months ago and it works way better then the standard. After switching I don't even know why they carry the standard GFO. The price works out to be about the same since you are using about 1/2 the media. Aside from far less dust, the biggest benefit that I see is running my flow rate higher. So more water passes through the reactor and it no longer clogs up. Before I was adjusting the reactor a couple of days. Wish I would have started with this product years ago.
PERFECT By PETER on 2/2/2018PETER would recommend this product to a friendPERFECT
High capacity GFO By William on 11/17/2017William would recommend this product to a friendUSE WITH CAUTION! This product works and works very well. Unfortunately it worked a little to well for me and stripped enough nutrients out of my tank that my sps corals started to bleach. By the time I figured out what was going on it was to late for the majority of them. I used the recommended amount for my tank based on the BRSF calculator. After a lot of research I found many other stories like mine. If you use this product in reef tank you should introduce it slowly. Gave this product 4 stars mostly because there is no warning on the potential problem it can pose to a reef tank. The product itself is 5 star and works very well.
HC GFO worked great By Carmen on 10/31/2017Carmen would recommend this product to a friendI had a phosphate reading of 5. Two days after starting the reactor it read .2 and the day after that barely 0. It may be zero now but it's been a few days since I've checked. Happy with the results. It was faster than I thought it would be.
Nice product By Kirti on 8/2/2017Kirti would recommend this product to a friendThis works pretty well and rinses clean very easily. Definitely ordering again.
I do not like it By Dunghan99 on 7/20/2017Dunghan99 wouldn't recommend this product to a friendI was using phosguard for a month a all my corals was doing fine, so I decided to try out gfo since they have very high review,only use half the recommend doses and after a week all my zoas react weird and some of them melted.
Effective and Efficient By Chivo on 6/13/2017Chivo would recommend this product to a friendI use this GFO on a BRS reactor with Carbon and it reduced my Phosphates to 0. When I get any reading (0.01 or more on my Hanna), I change the media an it immediately goes back to 0. Excellent product.
Excellent product By Carlos Vicente on 5/23/2017Carlos Vicente would recommend this product to a friendI have tried different brands of GFOs and BRS High Capacity GFO is the best of all. Worth every penny, don't waste your money on fancy name brands.
Worth every penny By Will on 3/21/2017Will would recommend this product to a friendI upgraded to this High Capacity GFO from the normal BRS GFO about 6 months ago. I get roughly twice the life out of this stuff which is important because I am lazy at switching my media and I travel for work a lot. So any time I can save working on the tank to enjoy it more is worth it in my book.
Low residues or particulates By Anibal on 12/16/2016Anibal would recommend this product to a friendVery high capacity last longer than regular brand with almost no residues.
Performs great at a great value By Allen on 11/24/2016Allen would recommend this product to a friendVery little dust, lasts much longer than other GFO and at a solid return for your money.
Starting at: $19.99
Starting at: $69.99
Will this product leach phos back in the tank?
It will not release back phosphates under aquarium conditions.
How much do u start out with in your reactor? Is there a measurement per gallon ratio?
It depends on how large your tank is. The easiest way to do the math is to use our reef calculator at the link below. You enter the size of the tank and the type of GFO you want to use, it will tell you how much GFO to add.
What is the amount of GFO HC you would normally run in a 120 gallon reef?
For a tank that size you would want to run 1 cup of GFO. The easiest way to do the math is to use the BRS Calculator right here:
Can the HC GFO tumble more than the standard, higher flow? I am also using the filter pads on the top to help keep the particles in better. Your thoughts would be great.
The GFO HC is a denser/harder product which means it can handle more flow without breaking down (though at the same flow, its tumbling characteristics would be about the same). If you are trying to increase flow you could also remove the sponge pads in the reactor when using GFO.
Will this work in a phosban 150?
It sure will. Its a great combo if you need something that is hang on back!
I been reading a lot about over dosing GFO and removing ALL phosphate thus starving corals. Is that an issue one should be concerned with when using this product?
Thanks for getting in touch with us in regards to having too low of phosphate to allow for healthy corals. If you are using this and are not supplementing in amino acids/ target feeding, there is a change of corals bleaching and dying off slowly due to low availability of nutrients that they need. Please let me know if there is anything else that we can assist with. Thanks!
Hello Folks, In my red Sea reefer 350, 91 gal total, I'll assume 80 gal or less total water, but based on a phone call to you folks, I purchased the 5" mini reactor and run about 1/2 cup ROX 0.8 and 1/2 High Cap GFO. My problem is, I'm wasting GFO it seems. The recommendation for the carbon is to change every 2 weeks, but the recommendation on the GFO is every 4 to 8 weeks. These don't match up well at all and I'm throwing away the High Cap GFO too early. Any better options ? I'm running one canister due to sump size limitations. Should I switch one of the two products ? thanks.
That's a great question! What we have found to work well for us is to cut the amount of gfo down based upon your change frequency. For example, if you change your carbon every two weeks, and would normally change your gfo every 4 weeks, just use half as much gfo as the calculator recommends and this will bring the gfo capacity more in line with your carbon schedule and avoid wasting extra media.
I'm a little confused about the notion of "how much to use." Since we are not adding anything to the tank water per se, what difference does it make how much we put into the reactor? Why not just put whatever amount we like into the reactor and then monitor phosphate levels to determine when to replace? Why do we need to calculate anything? Guess I have the same question for Carbon.
Do you need to rinse the GFO HC?
It is a good idea to rinse GFO quickly with tank water to wash off any small dust. Feel free to let us know if you have any further questions!
Will this product also remove silicates?
GFO will help to remove silicates from the water slightly. It sole purpose however is for phosphate removal.
Hi, I have a 150gal. Freshwater African cichlid tank setup. I am interested in buying one of your GFO reactors but not sure which one for my size tank and how much HIGH CAPACITY GFO should I use in the reactor? Also will this help keep down that brown diatom growth on my rocks?? Thank you for your help!! Mark
Overall you will use our aquarium calculator to find the correct amount between 2.5 cups for regular GFO and 1.25 cups for High Capacity. With this said you can use a single reactor for High Capacity and a larger reactor would be needed for the regular GFO. Feel free to let us know if you have any further questions!
How often does this need to be replaced?
How long can this GFO be stored in its container, before being used in the aquarium, once opened?
As long as it is stored in a sealed container and dry, it can last pretty much indefinitely. :-)
How many cups are there in the 1/2 Gallon (3.5 lbs.) of HC GFO?
There will be 8 cups in a half gallon container.
Does the high capacity GFO have to be tumbled in a reactor or could I place it in a media bag and put it in a high flow area of my sump?
It is best when tumbled in a fluidized bed reactor as the media otherwise has a tendency to harden into a brick, but even placed in a filter sock would be better then nothing.
Can I use the high capacity in a small tank (30 gallon)?
There isn't any minimum size limit to the high capacity gfo. It can be used in any aquarium it just happens to be more popular in larger tanks because you don't need as much media. Its handy when your trying to keep the equipment smaller while still maintaining the same effect.