GFO: time and amount in a reactor?

[ser_renely]

I am trying to figure out how long I should use my GFO for. It says it can last for months, but not sure I believe that.

How long do you use your GFO for in a reactor? and how much should I use? I use the directed about at the moment, but have found most directions to be off.

I have 65g of total water with a 'fuge, mixed coral tank, with SPS's.

Thanks,
Ser

[cnote2991]

I am curious what the consensus on this is as well. I started off using lower amounts than directed just to be safe, but just guess as to when I should change it out?

[sikpupy]

Your supposed to use a test kit to test your levels and change accordingly, however, i just read that if you have high P04, it gets exhausted in 10? hours.

[ser_renely]

I have found most test kits blow for p04...but I have only tried a couple. Always 0

[mutateddogbone]

generally people run about 1 cup per 100 gallons of gfo and replace it in a month. that allows your fuge and corals to absorb some of it without completely starving nutrients to the tank. the problem in the tank is not nutrients is the excess of nutrients that creates problems

[airdog67]

I made the mistake of adding to much gfo into my reactor imo. my tank has a total of 100gal, I added 150g or 5.30 ounces all at once. my po4 were around .5 and within 5 days my po4 were at zero. yeah to 0 phosphates but by removing my po4 to quickly I lost two sps frags. The rest of my tank and corals were fine, but next time I will add about half that amount to start out with. Ive been running the gfo for a month, im also interested about how long i should leave it in before changing, good luck.

[tmz]

There really isn't a measure or time period. It depends on how much phosphate is in the tank ,the product you are using, the rate of flow ,etc.. It can last hours or a month or more. The only way to know with come certainty when to change it is to measure the phosphate in the tank and the reactor effluent. If the rector effluent is lower than the tank then it is still drawing out phosphate. Many follow manufacturer's recommendations on the amount and just judge when to change it based on nuisance algae waning and resurging. Test kits are hard to read precisley. A colorimeter is easier but pricey.

[kb27973]

Yep I use a hanna meter and test P04 daily, when it starts to rise it's time to change. A cup lasts me about 2 weeks usually, but this is totally tank dependent.

Ken

[ser_renely]

Yeah, gfo seems tough to figure out for me.

thanks for the input guys. anyone else?

[eros]

I ran 150 grams in my 75 the first time I ran it. Luckily I never had a problem with my corals. It lasted a long time but the reactor was trapping detritus and was contributing to nitrates. Now I run 50 grams at a time and change it more often. I don't have a PO4 meter and the test kits have never worked for me so I just change it when I see an increase in algae growth and the glass gets dirty.

[Gdevine]

I change out 150 on my 65g every 8 weeks. I also do 12g weekly WC's and run Chemi-Pure Elite and carbon. No serious algae problems to speak of...

[ser_renely]

Yeah, I get A LOT of ditrus in my reactor as well. Think I might try changing it out more and use less.