Regenerating GFO

[dkeller_nc]

That's about right (just enough to move the GFO around a bit). Even if you've a particular setup with flow, reactor size, particle bed height, etc... that allows for a bit of phosphate to not be absorbed in one pass, that's not a problem.

Even with very modest flowrates, all of the tank's water's going to be processed through the reactor in a couple of hours, and so within a day or two the entire volume of the tank's water is going to be processed many times over (and so most if not all of the dissolved phosphate will be removed).

 

[elviraveloz]

Second time regenerating GFO and the particles turned an copper color. Should I use it?

 

[bertoni]

Hmm, I might give them an extra rinse, to see what happens. If you have a pH meter, you could check the pH of the rinse water, which might be interesting.

 

[elviraveloz]

It's 1000g. I left it overnight on 20 liters of RO/DI water 3 times already, being rinsing for four days already. I only have a high range PH reading solution, will that work?

 

[bertoni]

I wouldn't bother with the pH reading after that much rinsing. I suspect the GFO will be safe to use, although I'm not sure how much it'll adsorb anymore. I'd give it a shot.

 

[elviraveloz]

I use 190 grams of it yesterday, Phosphates before .07. Today reading is .02.

 

[bertoni]

Okay, that sounds like good progress!

 

[bheron]

i just did this again on a batch. this time didnt use my BRS GFO and instead simply soaked the GFO in a bucket with the solution for 4 days, occasionally stirring.

 

[elviraveloz]

I wouldn't bother with the pH reading after that much rinsing. I suspect the GFO will be safe to use, although I'm not sure how much it'll adsorb anymore. I'd give it a shot.

Like you anticipated, GFO only last a week, before regenerating use to last 3 weeks. I always keep it wet on original container. It may be Rowaphos brand it's not good brand for regeneration.

 

[bertoni]

Oh, well, another brand might be better for regeneration.

 

[bet77]

WTH? I can regen with 1 problem....... I can not get the media rinsed enough to get the PH below 10. In the beginning of the rinse the PH is nearly 11. I'm rinsing 4 cups of GFO at a time. Should I add some muratic acid to the rinse? Am I using too much LYE? Am I regenerating for too long?

 

[bertoni]

[welcome]

The length of the regeneration is unimportant at the rinsing stage. How much water are you putting through the media? It's probably okay to use as is, but you could rinse a bit of vinegar through it, if you're worried. If you use muriatic acid, then I'd be careful about rinsing that out, and of course, handling muriatic acid is dangerous.

 

[tmz]

I don't check th pH;I just rinse it untill there is little to no soapy fell to it. I don't think a little extra alkalinity will have a significant effect.

 

[bet77]

I'm using 4 cups of the High Capacity BRS GFO. I've neglected this system for a few years and I think my rock is leaching phosphate. The system is approx 350 gallons and 4 cups of the GFO last about 2 weeks. My first attempt of regenerating successfully removed all phosphate, but after rinsing with about 20 gallons of water the PH of my system spiked at 9.5.

This time around, I'm rinsing and testing PH, trying to get it closer to 9 before putting it back on the system. If it were a smaller amount of GFO, I wouldn't worry but with 4 cups it has a big impact.

 

[bet77]

I put the reactor in a 5 gallon bucket of RO water and used 1/4 cup of muratic acid and after 4 hours the output water's PH was 8.7. SUCCESS. Any reason that I shouldn't do this? Any better suggestions?

 

[bertoni]

That should be safe as long as you rinse the muriatic acid out well. That is a lot of media.

 

[tquinlan]

For those looking to do this that read the Advanced Aquarist article: please do not set up a reactor and a pump to circulate 1M NaOH through GFO. This is really dangerous, as you're pressurizing a caustic chemical that will burn your skin and eyes faster than you can rinse it off. All it takes is a hose barb connection to come loose to get sprayed.

Not really an issue with a small pump that produces maybe 2 or 3 psi of pressure into a canister/reactor rated for 100 psi of pressure. There are no hose barbs on the BRS reactor. They are the same John Guest compression fittings that nearly all reefkeepers use on their RO/DI systems (which run at much much higher pressure from tap water). A leak may present as a slow drip, it's not going to spray across the room and blind people.

 

[bheron]

Ok so this is strange. I decided to do a large batch of this yesterday. I worked with the same batch of GFO, used the exact same ingredients and proportions, but did the steps in a slightly different order. So why does one batch look so different than the other?



Again I pulled from the same batch of used up GFO, added RODI from the same container, and used the same NaOH source (Roebic Crystal Drain Opener).

The only thing I did different was the ordering of the steps in the process:

For the first batch I added the NaOH to clean RODI first, then dumped the GFO into the solution. Realizing that order meant a risk of some of the solution splashing up at me, I changed the order for the second batch. This time I ddded the GFO to the RODI first then added the NaOH.

A few minutes later I checked the buckets and they look totally different. Group 2 is what i expected to see.

Really curious if anyone has any ideas.

 

[david00061]

It just looks a little bit rusty to me. I don't think it's a big deal. Just rinse alittle more between sokes

 

[bheron]

yep, the rusty look is what I'm used to seeing. but why the difference? was it simply b/c I changed the order of how I added things?