Carbon?

[rhofmann]

I have a mixed reef with leathers, Monti, birds nest, a bunch of paly's and zoas, chalice, encrusting monti, turbinaria, candy cane, trumpet coral, acans and mushrooms (I may have missed a few). I have a bag of Chemi-Pure Elite in the filter sock that I leave in there all the time - change it every 3 months. I'm thinking about installing a carbon reactor and either putting the chemi-pure in there or switching to activated carbon. What do you guys think? Tank generally seems to be doing well - my xenia have melted on me, and the favia haven't really done much of anything for three months, otherwise the corals look healthy and are growing (slowly). I'd really appreciate any advice on this - I have heard that the leathers can pollute the water unless you use carbon, and the leathers in my tank are pretty large.
40G tank, 20G sump/refugium
Eschopps s-120
PH 8.3
Phosphate 0.25
Nitrate 5-10
KH 8
Calcium 420-440
Salinity 1.025
5G water change 1x/wk

[chefzilla]

I run carbon in a bag in my overflow and GFO in a reactor in my sump. If i was you i would just leave the chemi-pure where it is. As they say, If its not broke, Why try to fix it?

[rhofmann]

I've thought about a GFO reactor - do you think Phosphate 0.25 warrants using one?

[chefzilla]

What test are you using that says it .25? I try to keep mine at .005 using a hanah checker.

[rhofmann]

Just an API kit - I'm going to test the salt water that I purchase from Aquarium City - should have thought to do that sooner. I know API kits aren't reputed to be so great, but haven't run into any issues (that I know of) yet - maybe I just did....

[cngh]

how's your bio-load? be careful w/ GFO, especially if you have a small bio-load. too much GFO and you'll totally deplete your system of phosphate. if you deplete too fast, your corals will suffer. corals need a little bit of phos for food (not the scientific explanation, but that's my general understanding from what i've read). people who run ultra low nutrient systems or zero have to supplement w/ aminos or some other additive to put those things back into the water for the corals to absorb/use.

aside from food, phos comes from your fish poop, which is where it correlates to bio-load. a small bio-load together with a GFO reactor will pretty much guarantee an ultra low phos or zero phos system which will lead to your corals quickly losing some color or bleaching. if you have a large bio-load and/or you feed a lot, then yea, you might want a gfo reactor to balance the phos levels (but not to undetectable levels unless you plan to dose).

i've commonly seen threads that say to have the best sps colors, you need to keep phos below .04. however, i've seen pics of beautiful systems with awesome colors, large and small, sps and mixed, that routinely have phos above .04 up to .25 or higher. getting/keeping low phos is just one element, one part, of a larger maintenance regimen for the ultra low nutrient or zero nutrient guys. if you aren't tracking/testing the other things, then i doubt lowering only phos will do anything beneficial (unless it's super high, which yours isn't; or you plan to increase bio-load/feedings).

i just took my gfo offline because my corals were fading/bleaching. i'd used it to help control algae growth for a while and i only had a couple fish and my phos was always undetectable using the hanna checker (which had a +/- .04 margin of error). after about 4-6 weeks, my colors are starting to come back (i also added more fish).

i'd stick to chemipure elite or just plain GAC for now. like chef said, "if it ain't broke, why fix it?" in the meantime, get or borrow a better phos checker before installing a gfo reactor.

anyway, that's my 2 cents. take it w/ a grain of salt... opinions are like a**holes, everybody's got one. good luck and keep us posted on what you decide to do.