Great stuff! By Ronstopbl on 3/4/14Ronstopbl would recommend this product to a friendWas dealing with an algae problem that turned out to be caused by elevated phosphates. Guys recommended GFO and reactor so I watched the BRS videos and set to it! Made a very good investment-tank is algae free and I'm happier not looking thru slime covered glass. Gonna try the higher performance GFO next!
It works. By Kav on 3/3/14Kav would recommend this product to a friendBattling stubborn hair algae for a long time and finally decided to try this out after reading all the good reviews here. I still have algae now but way less and it isn't growing and spreading everywhere like before. Just a little patch. This stuff keeps hair algae in check! It works.
Great product! By Reefer Mike on 2/27/14Reefer Mike would recommend this product to a friendI think the Bulk Reef Supply GFO is the best you can buy. I have used it for 3 years. Great product. Phosphates stay at zero!
Definitely a good buy.
great product By chris on 2/26/14chris would recommend this product to a friendI buy this gfo all the time great stuff
Great Media By Gary on 2/23/14Gary would recommend this product to a friendA great media for reducing phosphates. Highly recommend using this product. Would suggest using in a reactor for best results.
Amazing Product By Edward on 2/4/14Edward would recommend this product to a friendIve tried a couple GFO's and I have to say this has been the best at keeping phosphates down. I ordered it with BRS carbon and the dual reactor. The best part was the price and knowing the reliability of BRS products.
Great Product By Samuel on 2/1/14Samuel would recommend this product to a friendI received this product in December and have been using it ever since. It has made a large impact on my phosphates and I would recommend it. It has lowered my phosphates to nearly zero.
gfo By kevin on 1/20/14kevin would recommend this product to a friendi use this in a brs reactor and it works great
great overall By Nicholas on 1/16/14Nicholas would recommend this product to a friendProduct is good, however I will choose the high capacity next time, because there seemed to be a lot of fines with the regular gfo.
Great stuff By Trevor on 1/15/14Trevor would recommend this product to a friendWorks great
Phosphates stay right at 0 By Matt on 1/15/14Matt would recommend this product to a friendI use the GFO in a fine mesh bag in my canister filter. It keeps my Phosphates right at 0 unless I feed heavily, then it pulls them right back down by the next day. The grains are very small, use a fine mesh bag if you need a bag.
This stuff is REEF MAGIC By Vince on 1/14/14Vince would recommend this product to a friendDon't even bother with the cheap imitators, this stuff not only is cost effective but it takes a while to deplete. Be careful to dial in the right amount or you can have a huge drop in your P04 and can harm some corals, I noticed I couldn't get my p04 under ~.5 until I ran this in a reactor which I only recommend.
Ask a Question About 'BRS Bulk GFO Granular Ferric Oxide'
Previously Asked Questions
by Paul on November 27, 2013, @10:19 AM
Sorry I didn't see the instructions, can you tell me how much I will neeed to use in your BRS reactor and how long between changeouts? I have a 90 gal tank and soon to be 125
Bulk Reef Supply Hey Paul,
The easiest way to know is to use the reef calculator at the link below. You just enter the size of your tank and it will tell you how much to run. In the case of your 90g thats about 1.4 cups (22 tablespoons). How long it lasts depends on how much phosphates you add to the tank (which is largely a matter of how much you feed). Pretty typical is 4-6 weeks though.
by michael on September 9, 2013, @1:58 AM
Should GFO be changed just as often as Carbon?
Bulk Reef Supply Hey Michael,
GFO should be changed when it is depleted. How long this takes will depend on the amount of phosphate that is added to the tank. A pretty typical tank that would usually be 4-6 weeks or so but the best way to tell is to monitor the phosphates. When they start to increase that would indicate that DI resin has reached its capacity.
by James on November 19, 2013, @7:22 AM
I want to mix GFO with carbon in the BRS single reactor. Is it OK to use the cheaper GFO to mix in with the carbon or do you need the high capacity GFO? I have a small system so I use low quantities of both carbon and GFO in my reactor. I was just worried about the regular GFO being too small.
Bulk Reef Supply Hey James,
It doesn't cause any issues with the reactor to use standard GFO. Really the choice just comes down to the volume of space you have to work with. If you have a large tank you may need more regular GFO then will physically fit in the reactor. Then you either need to get a larger reactor, or use the HC GFO which only requires half the amount.
by Jeff on January 2, 2014, @4:49 PM
How many cups in a pound of the BRS GFO?
Bulk Reef Supply Hi Jeff,
There is 4 cups in our 1lb container, 8 cups in the half gallon/2lb container and 16 cups in a gallon/4lb container.
by John Lasky on March 1, 2014, @11:28 AM
starting a 90 gallon . will also buy your reactor , how much product do I need to start out to fill the reactor. Thank John
Bulk Reef Supply Hi John,
The amount of media depends on the size of your tank with the maximum capacity of the reactor being 2 cups of media, though fortunately with your size tank you wouldn't be in excess of that. For a 90g tank you would use 1.5 cups of media. The easiest way to get measurements for most of these products is to use the BRS Calculator which can be found right here:
GFO comes in two types:
- 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 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 many 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 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 of a phosphate remover like GFO. 99% of all phosphate is added via foods added to the tank.
- 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.
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