Loading... Please wait...

Bulk GFO Phosphate Reducer SAMPLE Bayoxide (1/8 Gallon - 0.5 lb)

% Cash Back:
Free Shipping
Free Stuff:

Product Description

This GFO is the Original GFO Bayoxide E33. High phosphate levels are a recipe for disaster in saltwater aquariums. It is a nutrient for nuisance algae and also hampers the formation of calcium skeleton in corals. There are several different methods for dealing with phosphate levels but one they I like is using granulated ferric oxide (or GFO) in a media reactor. GFO is best used with a media reactor for several reasons.

Learn More About GFO

  • HIGH QUALITY: High quality ultra-pure virgin GFO for removing phosphates in water.
  • REDUCES ALGAE: Kills algae and prevents them from coming back by removing their food source, phosphate
  • RINSE BEFORE USE: Give quick rinse in RO water to remove any dust and fines.  Super GFO needs minimal rinsing.
  • SAFE FOR ALL AQUARIUMS: Works in salt water and freshwater aquariums & ponds
  • Bayoxide is a registered trademark of LANXESS Gmb, sold as a Co Brand with Kolar Labs

PRO TIP - When using GFO in a media reactor watch the flow rate of the water through the media. It does not need to be very fast at all. You don't want it looking like boiling water where it is throwing up small particles in the reactor. You just want the very top inch or less turning over ever so slightly like water right before a boil. Otherwise you will get GFO dust all inside your sump and possibly inside your display tank. Depending which reactor you choose, it is a good idea to run the output of the reactor into a filter sock. Worst case scenario some GFO fines get into the filter sock but this way you can avoid the disaster of GFO fines everywhere.

GFO Bayoxide® E33:


  • Standard Starting dose is 1 gram/gallon: best in fluidized reactor. EXAMPLE:  8 grams= 1 level tablespoon, 16Tbsp=1 cup.  1 cup per 128 gallons to start, 1 cup per 64 gallons standard dose. 
  • Monitor phosphates, add or change media when levels start to rise, or if algae increases.  Sometimes the algae consume so much phosphates the levels test low while algae growth is still present.  Once break in period is over, continue increasing until algae is controlled, or switch to High Capacity for stubborn algae problems.  For optimal effectiveness, do not allow overall Phosphate levels to test above 0.05ppm.  Test water coming directly from the phosphate reactor for phosphates.  If any phosphates are present, GFO should be increased or replaced. 
  • For best results, Pre-filter water going into reactor, and water going out (example: filter sock on effluent to trap fines, especially with new media).  Pro tip:  Remove all sponges before and after media in reactors and replace with plastic mesh to prevent clogging.  Add small check valve to pump side of water line/keep return line submerged, to prevent back siphoning into pump in a power cut.
  • Rinse all new media and discard discolored water from rinsing before use. Pro tip: Use bucket full of tank water and submerge pump and reactor in it.  Run pump with return line running to drain until discoloration stops, then return line back into bucket.  Run for a few minutes checking for proper fluidization.  Check for Air bubbles or pockets, and gently tap or tilt reactor to eliminate them.  Return pump and reactor to sump or tank together. 
  • Check weekly for good flow and fluidization.  If clogged, dump reactor contents into 5 gallon bucket with tank water, stir and poor off debris.  Media can then be returned to reactor in part or whole. Pro tip: Use this technique when changing media, and save approx. 1/4 of old media to mix into new media, keeping bacterial cultures stable to prevent bacteria or algae bloom from media change.  If used in canister filter, use micron bag to hold GFO preferably in thin layers to keep good flow, and reduce channeling through media.
  • If any negative coral reaction is noticed after new or changed media, reduce amount by half.  Dropping phosphates too quickly can cause shock, once established, overdose is unlikely and phosphates will not leach back into system.

Customer Reviews


Why Choose to Shop with Us?

  • Pay with Amazon Pay - No need to type in billing, shipping addresses or credit card info, just log in to amazon and select the info you already have saved with amazon to purchase from us! Easy, simple and quick.
  • Fast & Free Shipping - No Minimum Purchase, Our Free Shipping option averages 2.3 days in transit.
  • Same Day Shipping - All Orders placed before 1 PM EST ship Same Day. Meaning your tracking will actually work the same day as your order.
  • Free Stuff - We offer tons of Free Samples, Shirts, Stickers and plenty more just for giving us your business!
  • 5% Cash Back Rewards - There are no Preferred Clubs or Groups to Join.
  • Free 2 Day Shipping - Free 2 Day Shipping on Products $35+ from select manufactures.
  • PayPal Financing - Want to buy a new tank without having to pay for all of it upfront? No Problem, use you PayPal Credit program to spread out the payments.
  • Free Returns - Returns of any Items (Both Brand New and USED) within 30 days are Always FREE!
  • Apple Pay - You can checkout with Apple Pay, submit your order with your thumbprint and we will never see your payment information. Awesome!
  • Military & Civil Service Discount - As a small token of our appreciation, we offer a Military & Civil Servant discount. A Bonus 5% Reward Points on 90% of what we carry. deeply appreciates all military men and women & first responders for their service.
  • Automatic Price Matching - Just click the Price Match button under Add to Cart. No need to email your price match.
  • Text Message 717.408.8337 Support - No one uses the phone anymore, just text us 717.408.8337. We will do our best to help!
  • Live Chat - We offer LIVE WEB CHAT Mon-Fri 9am to 4pm EST. Get instant access to our customer support & your questions answered.
  • Credit Card Security - We do not keep any Credit Card Numbers on File. Our checkout page is plugged directly into paypal credit services so we don't even know your card number when you order. 
  • Website Security HTTPS - Our entire site is HTTPS Secure, not just the checkout page. Your entire browsing session is encrypted and secure. We have an ESV level SSL Certificate which includes business identity authentication, strong 256-bit encryption, 2048-bit root, $1.5M USD warranty & a GeoTrust dynamic Secured Seal trust mark.

Have questions? Just ask - or Text Message us at 717.408.8337