HC GFO. How much does one pound amount to.
 

How much volume does one pound of hc gfo amount to? How much do you use for say a. Medium stocked 80g tank. How often to change it?

Is it light like carbon?

The reason I ask is I want to add it to my system and don't know how much to order. Most places I find sell it in 1 pound cases. For around $25 per pound. Depending on order amount of course.

Thanks for any info.

I just weighed some of mine for you and it dials in at 220g per cup (250ml)... So call it roughly half a pound per cup. When first adding HCGFO to a system I use roughly 1 tbsp per 8 gallons (so for you that is roughly 150ml or 0.5 cups). You could even go with a bit less. After 4-8 weeks, add another 150ml (so that you're running 2 tbsp per 8 gallons). Err on the side of too little than too much. You can easily shock your tank with this stuff. I accidentally killed off a few SPS colonies when I first started using it because I used just a bit too much.

Excellent info thanks!

Here's a calculator
http://www.bulkreefsupply.com/reef-calculator

Didn't know brs had a gfo calculator.

Thanks for the tip.

150 mL of high capacity GFO for an 80-gallon tank is too much for a first dose imo. I would try a third of that at first. Stripping a tank of phosphate really fast is a really bad thing - especially if the phosphate has been high for a long time.

From Get Rid of Hair Algae & other Nuisance Algae in my signature (referring to normal capacity GFO): We're gonna be safe and assume there is a lot of phosphate in your water, so add about 1 mL GFO per gallon of water in your reef. In 3 weeks add another 1 mL/gal to the existing media. In another 3 weeks (6 weeks total) dispose of all the old media. Refill with 2 mL of fresh GFO per gallon and let it run for 6 weeks. Dispose of old GFO and refill with 3 mL GFO per gallon and let that run for 6 weeks. Usually 3 mL GFO per gallon is a good maintenance amount, but some people use significantly more or significantly less. You will learn when you have to change it out because you will start to see some algae growing usually on the front glass is the first sign, and adjust the amount of GFO you use so that you can change it every 4-6 weeks.

What she said. Like I said, aim on the low side.