GFO are my calc right?

Tab28 · Jul 18, 2011

I recently got my shipment from BRS and decided to get their GFO since it seems much cheaper. I have used the commercial brands for years but seems in a much smaller amount. If my calcs are correct for my 130 gallons I should be using 2 cups of the GFO and after about 8 weeks I can increase it to 4 cups. Is this correct it seems like alot compared to more commercial brands. I hope it works better since at the quality I would need a larger reactor.

clowndude · Jul 19, 2011

You are correct. I just checked the calculator on BRS and for your tank it is 2.03 cups. Be careful that you don't add to much at first.

Note, if you are running the GFO HC it is 1.02 cup(s)

cdness · Jul 19, 2011

Start out with a little bit and work your way up. You may not need to get to full strength if a smaller ammount will control it for you. To much and it will shock the tank.

Also rinse it well. The BRS stuff has lots of dust particles.

Tab28 · Jul 19, 2011

Thanks for help. It just seems that 2 cups was alot compared to other brands. I did not want to shock my systems so I did not plug in pump until I verified the amount. If I have to go full strength which is 4 cups I will need another reactor.

myzislow · Jul 19, 2011

Remember that GFO has an affect on your overall Alkalinity level so be careful.

"Many aquarists using GFO have reported unusually extensive precipitation of carbonates on the solid GFO, and elsewhere in the system. Such precipitation can, for example, be a contributing factor in the caking of such materials, and can coat other surfaces in the aquarium. This precipitation can also contribute to a drop in alkalinity and possibly pH as it removes carbonate from the water column. The effect of calcium will be similar, but smaller on a percentage basis, with a drop of only 20 ppm calcium for every 1 meq/L (2.8 dkH) drop in alkalinity. Increased calcification by corals and coralline algae (possibly spurred by reduced phosphate) can also cause similar drops in calcium, alkalinity, and pH."

Reef Breeders · Jul 19, 2011

That usually only happens when over five times the reccomended dose is used, you will be fine.

AZDesertRat · Jul 20, 2011

NEVER use the BRS recommended amounts, they recommend twice the normal dose and its WRONG.

I don't know where they came up with that except they get to sell you more.

FULL DOSE is 10 grams per 10 gallons of tank water, thats equivalent to 1 level tablespoon per 10 gallons.

Start out with one half that dosage or 1 spoon full for every 20 gallons, in your case it would be 6 or 7 tablespoons full for the first month or two replacing it every week or so in the beginning then work up to the 13 spoons after that. 13 spoons or 130 grams is nowhere near two cups full I don't believe.