Regenerating GFO

OK, I've been reading this and getting real confused. Do I want 1M or 0.1M or somewhere between? I understand to mix 40 g to a liter (1 M) or 4 g to a liter (0.1 M). How long do we leave it in this solution?
 
Based on our testing 12L of 1.0M NaOH (dissolve ~450g of 100% lye in 3 US gallons)

leave it in 96 hours

the proccess is easy, soak GFO in vinegar overnight then in lye dillution for 4 days stirring GFO now and then if you dont clean in a reactor
 
Alright, I'm not sure if I ruined my old GFO. I put about 250 gams of GFO in a container and filled container up to GFO level with RO water and then added 5% distilled white vinegar so that the water was 1:1 with the vinegar. I let it sit for a few minutes and then dump the brown colored water. I then added just the vinegar until it was twice the height of the GFO. I left it for an hour. Then I dumped the vinegar out and starter to rinse. I started with RO water, but after filling and dumping it about 10 times and the water didn't seam any cleaner, I switched to tap water. I've probably done this about 50 times, no lie and the water is still getting completely brown. Why won't it rinse out?
 
The vinegar was too strong. You must dilute it. Did you have the pellet type of GFO?

DJ
 
I think I figured out what happened with the vinegar. I did have some RowaPhos (very fine stuff) that I mixed with the GFO. I think the batch I put in the vinegar had some of the RowaPhos mixed with it. That seams to be what is coming off. I sifted a small amount of the mixture through a shrimp net and most of the tiny particles are gone and it seams to be rinsing clean now.

I found some Lye locally, so I mixed up a 1M solution. In the next couple of days, I plan on pulling the GFO (pure GFO) from my reactor and soaking it in this solution for about 4 days, unless somebody tells me a better time frame. We'll see how that works.

I simply used my old BRS 2lb GFO container to mix 1 L of 1M solution and it works fine.
 
Cool. Consensus, from what I've gathered reeading thru the entire thread, seems to be 2-4 days depending upon how thorough u want to b. Just keep in mind that longer recharges take their toll on the grain surface of the GFO.

DJ
 
Hello guys. I just recharged my first batch of gfo. It was brs but not the HC quality. My question is after I rinsed the batch after sitting in solution for 4 days the gfo is really soft and will disintegrate if i squeeze it. Is this normal after sitting in NaOh solution?
THanks
 
I've just started my first recharge today. Maybe I'll only do a day in the solution. I'm not sure if it's normal to be soft maybe 4 days is too long. But GFO is normally soft, that's why it has to be in low flow because the high flow with grind it up.

Did the GFO rinse clean? If so, it may be fine. Oh, and mine is BRS pellet GFO, but not HC.

Also, what did the solution look like after the GFO was added. I was expecting the water to get nasty, but it didn't. After a little while, there was like three layers in the container: GFO on bottom, a light brown cloudy area, then the clear solution on top.
 
I've just started my first recharge today. Maybe I'll only do a day in the solution. I'm not sure if it's normal to be soft maybe 4 days is too long. But GFO is normally soft, that's why it has to be in low flow because the high flow with grind it up.

Did the GFO rinse clean? If so, it may be fine. Oh, and mine is BRS pellet GFO, but not HC.

Also, what did the solution look like after the GFO was added. I was expecting the water to get nasty, but it didn't. After a little while, there was like three layers in the container: GFO on bottom, a light brown cloudy area, then the clear solution on top.

I'm beginning to think that 48 hrs is enough. I wonder if circulating the solution would help with saturation and be easier on the overall structure of the grains - like maybe with a real small power head in an airtight container.

DJ
 
I rinsed off the GFO after being in the 1M solution for about 24 hours. Before I rinsed it, the GFO looked fully intact on the bottom of the container, with a light brown (1/8") layer of haze on top, then the crystal clear solution. If I swirl the container the haze mixes with the solution and creates a light brownish unclear solution, which settles back after time.

How do I know that the PO4 was removed? I tested the clear solution with my crappy API kit, but it didn't register any PO4. Is the haze possibly the removed PO4? Can anybody that has done this process please explain if this sounds about right?
 
I am also unable to measure the amt of po4 that was removed from the gfo that i am regenerating. Testing the clear solution gives a reading of 0 on my salifert kit. Testing the stirred solution also gives 0. I mixed 10 tablespoons of caustic soda in 5L of di water and the ph of the solution is 12.3
 
I am also unable to measure the amt of po4 that was removed from the gfo that i am regenerating. Testing the clear solution gives a reading of 0 on my salifert kit. Testing the stirred solution also gives 0. I mixed 10 tablespoons of caustic soda in 5L of di water and the ph of the solution is 12.3


I am not sure about Salifert but our PO4 test requires that the pH of the tested sol'n is between 2-10.

If you dilute it down by 100x it's likely you won't need to neutralize it, but if you still do HCl or vinegar will work.

Advanced Aquarist should be publishing our article in next month's issue.
 
I am not sure about Salifert but our PO4 test requires that the pH of the tested sol'n is between 2-10.

If you dilute it down by 100x it's likely you won't need to neutralize it, but if you still do HCl or vinegar will work.

Advanced Aquarist should be publishing our article in next month's issue.

Exactly. You have to bring down the overall pH of the solution to be tested or it won't register.

DJ
 
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