Regenerated gfo

[Cory]

I regenerated my rowaphos with lye. I'm worried about the high ph when I put it in my tank. Can I rinse it with vinegar or muriatic acid? If so how?

 

[Randy Holmes-Farley]

If you've rinsed it well, that shouldn't be an issue, but a quick dilute vinegar rinse is probably ok. It will dissolve in too much acid.

 

[Cory]

Thanks Randy! Just wondering though how much should I rinse with ro/di? It's only the small container if rowaphos. 8oz? Gallons? By the way this is boxfishpooalot

 

[Randy Holmes-Farley]

Hey, box!

If you have a pH meter you can monitor the wash.

If the pH is below 9 it is fine. Even 10 may be ok.

With pure water, how much it takes depends on how well you drain it between rinses.

 

[Cory]

Hey, box!

If you have a pH meter you can monitor the wash.

If the pH is below 9 it is fine. Even 10 may be ok.

With pure water, how much it takes depends on how well you drain it between rinses.

I don't have a ph meter yet unfortunately. But what if I let it soak in 3 gallons of ro/di 3 times. Sufficient?

Or should I do a dilute acid wash too?

 

[Randy Holmes-Farley]

How much GFO?

 

[Cory]

How much GFO?

Its approximately 50ml worth of the 100ml can of rowaphos. It's strange they use ml for a something solid. Why not grams?

RowaPhos Phosphate Removal Media - 100 mL

 

[Randy Holmes-Farley]

3 gallons should be plenty, but it will work better as more smaller rinses.

Say 6 rinses of 0.5 gallons each. Try to pour off or drain as much water as possible each time.

I wouldn't bother with acid. If a little base is left, all it will do is give a small boost to pH and alkalinity.

 

[Cory]

Thanks a lot Randy! Fwiw I tested the phosphate with an api po4 test kit and added 12 drops instead of the usual 4 (to bring the ph down) and po4 was black on the color chart where the highest on their chart is dark blue. So I'm assuming the process worked.

 

[Randy Holmes-Farley]

OK, sounds good.

Happy Reefing.

 

[Cory]

OK, sounds good.

Happy Reefing.

Any problem with leaving it outside in the cold for the fumes? It's almost freezing here in Canada, about +2 C. Also can you please tell me how many grams of lye for every gallon of water? I feel I'm wasting it.

 

[Randy Holmes-Farley]

The cold won't hurt it, but what fumes are you worried about? Lye doesn't have fumes. Vinegar does if you use that for the pretreatment.

I don't have a specific recipe, so I'd look to the threads where folks have used it. One that is commonly used is 3 tablespoons lye per liter of RO water.

 

[Cory]

Initially when I add it to ro/di with the rowaphos in it the water gets hot. If you put your head overtop of it there is a strong gas that kind of slightly burns the nasal passage. Maybe it's the organics on the gfo. What I've read is the water needs to have 1m of lye. Micro molar?

 

[Randy Holmes-Farley]

The concentration I suggested is about 1 M.

Does it smell like ammonia?

 

[Cory]

I like Ed the smell to the exhaust of a diesel truck. Is there a possibility for ammonia? I used "pure" lye crystals.

 

[Randy Holmes-Farley]

I'm not sure what the smell would be, but high pH converts ammonium to ammonia which is more readily evaporated and smelly.

 

[Cory]

Where would ammonia come from?

 

[Randy Holmes-Farley]

Degrading organics left on it if it has been sitting around wet. I don't know if that happens, but it might.

 

[Cory]

Ok. Well I left it outside and we had a snow storm! It didn't freeze either with that lye in it. But I noticed the GFO has a lot of white rusty precipitate.

How many lye washes do you think is necessary to remove all the bound po4? I do it 3 times. So far it's worked great (the first batch) keepmg po4 undetectable via salifert.

 

[Randy Holmes-Farley]

The white ppt may be calcium carbonate, which is why some people give it a vinegar rinse as the first step.

I don't recall how many washes people usually use (some I see use only 1) and 1 may be adequate.