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jarrett shark
09/29/2010, 08:35 PM
Yeah that right 2.5+ !!!!!!
my hana meter only goes up to 2.5
well i have a 500gal FOWLR with 2'' sand bed that i just removed the sand a week ago. I thought the sand bed was the issue. I do have very minumuim LR (60lbs)and mostly use bioballs in my sump. Well i am converting the tank to reef and I am stuck for words how to reduce quick. I used a week ago Brightwekk Phosohate-E removal and that did nothing.
I have been doing 100gal water changes 1x a week

I just finished installing a media reactor and not sure if i should use phosband or Bio pellets?

How do ou know if phosband is saturate in were i should change it?

i want to add Live rock that is cured already but not sure if that will make it worse.'

My last result is a 90% water change

teebs
09/29/2010, 08:50 PM
Yeah that right 2.5+ !!!!!!
my hana meter only goes up to 2.5
well i have a 500gal FOWLR with 2'' sand bed that i just removed the sand a week ago. I thought the sand bed was the issue. I do have very minumuim LR (60lbs)and mostly use bioballs in my sump. Well i am converting the tank to reef and I am stuck for words how to reduce quick. I used a week ago Brightwekk Phosohate-E removal and that did nothing.
I have been doing 100gal water changes 1x a week

I just finished installing a media reactor and not sure if i should use phosband or Bio pellets?

How do ou know if phosband is saturate in were i should change it?

i want to add Live rock that is cured already but not sure if that will make it worse.'

My last result is a 90% water change

1st thing to do is to remove your bio balls and give them a thorough cleaning. Most likely a lot of detritus is trapped within them and thus becomes a phosphate factory. Give your sump a thorough cleaning also.

Next is to use GFO such as rowaphos or HC GFO from BRS and run it in a reactor. This will help reduce PO4 also. This will be very expensive and you might have to use quite a lot of it so you may want to regenerate it using caustic soda.

You may also want to try using lanthanum chloride to reduce the PO4 levels.

Yogre
09/29/2010, 08:53 PM
With phosphate that high, I doubt bio-pellets would be a good way to start out. I'd suggest running LOTS of GFO, and plan on changing it out quite frequently, at least at first.

You may want to look at dosing some of the lanthanum chloride PO4 removers into a filter sock, as well. LaCl2 is pretty efficient at binding PO4.

You've already removed your sandbed, and you don't have a bunch of rock in your system, so I wouldn't think you'd have a horrific amount of PO4 entrained in your rock. I wouldn't add new rock until you get that PO4 down, or it'll just get into your new rock and slow down the cleanup time.

But yes, that's a lot of PO4 and it'll take a bit of work to clear it up.

skunkmere
09/29/2010, 09:34 PM
why not carbon dosing? it looks like you are going to spend a fortune on media. do you have a good skimmer?

Yogre
09/29/2010, 09:49 PM
The experience I've had (which is admittedly limited) with carbon dosing is that it is much more useful in controlling lower levels of PO4, as the Redfield ratio on which the theory is based (again as I understand it) is 106:16:1, C:N:P.

Seems to me to reduce PO4 rapidly from really high concentrations, the quickest way to go is LaCl2, followed by GFO, then carbon dosing for PO4 cleanup.

The GFO required will indeed cost a bit for a 500 gallon system.

bertoni
09/29/2010, 10:21 PM
Since the tank has no corals, using either GFO or lanthanum chloride should be fine. I don't have enough data on hand to determine which would be cheaper, but I suspect you'll need to keep GFO in the system over the longer term to keep the phosphate level down.

Carbon dosing might do the job, but it'd take a very long time, and might require dosing a nitrogen source.

jarrett shark
09/30/2010, 05:05 AM
so how do i know when phosband needs replacing?

Also were do i get LaCl2

Yogre
09/30/2010, 05:37 AM
so how do i know when phosband needs replacing?

Also were do i get LaCl2

Bluelife makes a lanthanum chloride PO4 remover, as does Magnavore.

The only way to know for sure that your Phosban, GFO or other product needs replacing is to test the effluent of your reactor. If you have PO4 in your effluent, your media is exhausted. I'd say though that with really high PO4 levels your media will be exhausted within a couple of days at first, just change it frequently. As PO4 levels fall in your tank, you can leave the media in longer.

bertoni
09/30/2010, 03:30 PM
Testing the effluent is the easiest way when the phosphate level is fairly low. If you're using a lot of the media and the phosphate level is very high, just testing the tank and checking the downward slope of the phosphate curve will be fine, too.