I am going to run GFO in BRS reactor from the beginning. Should I run carbon as well? I am getting the two chamber reactor.
I'm a little late here but to chime in but I hope not too late.
First off you'll spend a Fortune in GFO to clean the PO4 out of this stuff if you get a batch like mine and carbon would probably just slow the cycle
I would HIGHLY recommend NOT curing this rock in your new tank Especially if you plan on treating with LC. There are methods of doing it but that would require many 5 micron socks and a LOT of time changing them to contain the precipitates.
When I went through the LC dosing EVERYTHING was covered with the precipitates... I couldn't imagine trying to clean the stuff off your overflow, DT and sump interior (the inside of your plumbing and pumps) No one really knows the effects of the precipitate on some of the more sensitive creatures we tend to keep in our tanks
Do this: (I wish I would have taken more time on this but so far it's working out well... I'm the OP BTW... my account got borked)
1: When you get your rock place in one or more containers big enough to hold it all (30gal Brute cans work great) It wouldn't hurt to hose it off first
2: Fill with salt water and drop a heater and power head or two in there (a Power head on the bottom is better for flow)
3: Let cycle ~4-5 weeks until you get a zero reading for nitrites. At this point your rock is cycled and ready to take care of a light bioload. However, you still may have a phosphate issue...
4: Test for phosphates, no matter the reading do a 50% water change, test again (keep notes)
5: Wait 48 hours and test again. If the readings have increased then decide if you want to dose LC. If they haven't don't bother
6: If you decide you are dosing just dump a TBS in at a time. After a few minutes the water will turn cloudy with "snow" Let this settle out until the water is clear (this will take a day of two to settle)
7: Repeat #6 until the water no longer turns cloudy
8: Rinse rock THOROUGHLY with SW
9: place in tank, wait a few days to be sure you still have zero Ammonia and Nitrites
10: add clean up crew