biochemistry question: what DOES a fuge sop up? My own guess...

[Sk8r]

...is that in addition to phosphates, which the algae uses for fertilizer, it will also uptake nitrogen [nitrates] and potassium, which is what is in commercial fertilizer: nitrogen, phosphorus, and potassium.

Nitrogen is available in such amounts that, indeed, we can easily toss that out and know we have more; we don't want phosphorus, as I understand---I know my corals don't appreciate it; but what about potassium? Is that a loss we should ask about? Do we possibly need to supplement it back, if we have a fuge in a closed system?

And to what degree IS loose nitrate part of the uptake?

Does anybody have any info?

[Mike O'Brien]

There is some info on caulerpa in this one from Dr. Ron

http://reefkeeping.com/issues/2002-1...ture/index.php

[Sk8r]

Extremely interesting.

also some info in there re presence of heavy metals in artificial salt mixes and buildup over time...I think of the days back in the 80's when running polyfilter was just routine. I wonder if adding that to the regimen of occasional things to do might not be a good move. It is good at nabbing metals, and of things not particularly desired in the tank, that algae aren't that great at sopping up, seems that metals are an eventual problem for long-lived tanks.

By this article it does suggest that a fuge does sop up a whole variety of things for export, and that xenia can do a really good job as well. It, like caulerpa, is subject to sudden deterioration and release of what it has gathered. But it is a very efficient export method.

[bertoni]

I don't think that algae consume potassium at a large enough rate to be a problem. Water changes seem to be enough.

Nitrogen is a macronutrient, and there should be analyses of the dry content of varous algae somewhere.

[WarrenAmy&Maddy]

thanks for the link fr Shimek

too bad there were not more comparative tests done like this...

would espec like to see how chaeto stacks up against caulerpa - although from what i understand it doesnt quite compare (in nutrient export) but yet has less 'toxic' means or less trouble in the end using chaeto (re associated problems using caulerpa).




here is a quote from the article
(ron shimek)

"Aquarists often worry about the removal of nitrogen products from their systems, but it is clear that several of the export methods are fairly efficient at removing nitrogen compounds. On a per weight basis both skimmer sludge and Xenia export significant amounts of nitrogen, probably as protein in bacteria and tissue respectively. Comparisons utilizing carbohydrates are incomplete, but tend to indicate that Xenia was again the most efficient export of these materials."

"Export efficiency may be measured in a couple of ways, however, and although on a per weight basis Xenia appears to be the best export mechanism, Caulerpa grows far faster in most tanks and it would accumulate a lot more of the needed export per unit time"


in my system... = a nitrate reducing factory!
xenia far outgrows the chaeto (for whatever reason)... and since this system has been established i have yet to detect nitrates - even when checked against tests at lfs... and that even includes during heavy feeding (like for last 2 mos since feeding multiple times/day - after getting anthias)...

dont know if its the xenia
or DSB in both display/fuge... or over 200# of LR - as much as it is a combination of all the above.

based on the rate the xenia grows
my 'hunch' is that the xenia is taking a lot of something out of the water column (doesnt take a rocket scientist to figure that out)


given xenia has its own problems too
mainly growing into pest proportions... only keep a small patch of it in the main display and as its trimmed it gets thrown into fuge to attach to LR rubble (then traded at lfs store credit)...

at one point my entire 50gal dedicated fuge
looked like a xenia forest - still does to some extent but for good reason!

here is a photo of the 'xenia' fuge in its infancy


my skimmer has not been working
for probably 10days or so since have been too busy w/ holidays and/or too lazy to take it apart and clean it (its a worthless berlin red sea turbo skimmer which needs to be taken apart and cleaned every few days or it stops working - might as well just say i dont have a skimmer to begin with! )...

have been monitoring my water parameters
though more closely then normally do (just out of curiosity w/ skimmer not working)... nitrates are STILL zero - although my phosphates have started creeping back up again - realized time to change out media in phosphate reactor and my rodi - di cartridge needed to be replaced again!

once my phosban comes in next few days...
(already replaced DI cartridge) then i am going to - for an experiment... start running my 210gal system SKIMMERLESS (not much different then what already doing!)...

skimmerless bec
want to see how effective/efficient everything on this system is running... as far nutrient export is concerned... again i feed heavily atleast 2-5x/day ( feeding anthias) and its going to be interesting to see how the system will respond...

my feeling is that i dont need a skimmer
but this will be the test...

regards

[cloak]

I don't think nothing. Why can't you keep a successfull reef without a fuge? Don't really need a skimmer.

JMO.