i haven't heard carbon becomes exhasted after 2 weeks as fact before, i must say i wouldn't be impressed it i bought it! truth is unless u keep taking samples back to the labs every week, no one can accurately say how long carbon can run for. there are only guides set by both manufacturers and reefers experience alike! with u trying to determine whats happening in the middle ground!
u would have to know what carbon absorbs in
your system for one, then be able to test for it for two! testing
DOC rating would not be able to narrow it down to the carbon alone! there would be a greater variety of
DOC's in a system that has loads of macro algie growth, as compared to one with very little., and even harder to narrow it down if u are using a
skimmer!
this is my opinion of course, someone might opt to tell it other-wise
a more likable fact is the volume of raw water that is coming into the carbon reactor without pre-filtering the more u should recharge in frequency.
the best guess as to how effective it is, is based on a visual que!
for example, the clarity can be guaged by a strip of white plastic, that u have coloured one half light yellow, unless its marine safe marker dont put in the water ok, so prob best to attach it with blue-tac to the glass, and look from a distance. when u can no longer gauge the white from the light yellow u know where your at!
only a 2 sec test! if the visual benchmark is set, u know whether u need to run it or not, or whether u dont have enough product in the flow or not, or whether u need to recharge it. u will be the judge of this!
i would not run it constantly if u keep stony reef building corals, cause it takes out good substances like
trace elements ect ect indescriminately, but id rather voice a common thought of a couple times a month!
the couple of brilliant geezers named Nilsen & Stuber published their finding some time back of how detrimental constant running of carbon is to Acroporidae & Pocilloporidae, or soft corals like Xenia.
we used to run it 24/7 open 365days a year as standard many years ago, but the thinking has changed totally in regards to this i believe.
another like-able fact is that water flowing or pushing though the medium is the best way for carbon to run, thats why i opted for using a canister filter to run it. very easy, grarenteed flowthrough, and its a add-on to the system that doesn't interfer by redirecting water flow in the
sump.
u put the pipe intake of the carbon reactor at the base of the output from the overflow, the output of carbon treated water into the baffel where the intake for pumping in the display is located.
waters only treated once in that cycle, it couldn't be simpler, and u have the total control over the unit with minimal messing about! another way is to use a water tap treatment purifying unit filled with carbon.
as for how much to use, well this depends on the type of carbon used, the manufacturers that made it, how fine or course the material is itself giving rise to how absorbive it becomes after treatment to become activated. the rule of thumb from the likes of even older geezers Wilkens & Birkholz, its suggest 500grams per 100lt of water. this is a very rich figure indeed, but use this as the max figure and work downwards.
group buys can save u on the products, i think we can get it down to $6-7 per kg delivered here from the pharm companies.
ok, i new i had a hard copy of this report somewhere, i have looked online to see if its active still, it is, have a read buddy!
http://www.pets-warehouse.com/carbon.htm
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