View Full Version : Protein skimming for freshwater?
MasterBlaster
12-06-2004, 5:10 PM
I read somewhere that the lack of salt stops fresh water from fractionalizing and producing foam, thereby rendering it ineffective. I hate to put my skimmer in the closet if it will work in my new freshwater tank.
Does anybody out there use a skimmer in their FW tanks?
Seaman
12-06-2004, 6:00 PM
Everyone says "it wont work, there's not enough surface tension in FW" well in my heavily stocked tank I wanted to see how well it would work, so I hooked it up and as expected I diddnt get the nice thick foam like in a SW tank, but it was still foam and it was darker in color, so it was doing something.....I think it depends on the amount of dissolved organics in the water, with quite a bit I think it can still be fairly benificial to use....but in a lightly stocked tank it wouldnt be worth it......
But like I said, most will say its useless, but I got foam, and it was dark....so IMO that means its doing something!!
MasterBlaster
12-06-2004, 8:44 PM
Fugging A, bro. If you got any dark fluid than you've removed crap.
Cool! I'm gonna hook it up! I wanna carry a heavy bioload! :dance
Seaman
12-07-2004, 12:21 AM
also what type of skimmer do you have.....I'm not sure which ones are more effective, but mine is an "injector" type....DIY
Here's a diagram and picture of mine:
The red is where the skimmate exits, the blue arrow going in, is the inlet into the injector and it forces the water which mixes with the air in the chamber and forces it down and over to the skimmate chamber. Like I said though its not the same as the nice thick DARK foam you get on a SW tank, but it does have a darker color and rises to the collection area....FWIW
http://www.sunrift.net/modules/xoopsgallery/cache/albums/20reef/nano_skimmer.sized.gif
http://www.sunrift.net/modules/xoopsgallery/cache/albums/20reef/skimmer.sized.jpg
Under "normal" tank conditions, foam fractionators don't work in FW - bubble size and the physics of the operation are against you. But with heavy organics from high bioloads, they certainly will pull stuff from the water. Koi folks have used them for years on their overstocked ponds - really massive units. But it will still not be as effective or efficient as in SW/high BW. You will get rid of some of the excess, but not down to the level of SW operation. You will need a lot more unit for somewhat less effect. But in high organic setups, everything helps, right?
slipknottin
12-07-2004, 3:16 PM
they will also provide great oxygen exchange for those heavier stocked setups.
Seaman
12-07-2004, 8:25 PM
but def. not good for a planted tank.
MasterBlaster
12-07-2004, 8:50 PM
but def. not good for a planted tank.
Why? Too much nutrient removal?
MasterBlaster
12-07-2004, 9:02 PM
Nice looking DIY skimmer, Seaman.
A foam fractionator will strip the water of CO2 quickly, down to atmospheric equilibrium - from 2-5ppm depending on your elevation, the current pressure, etc. Carbon is >40% of a plant's dry mass. Aquatic plants only get that from dissolved CO2, supplemental gas CO2 (pressurized or DIY fermented), or one of the special supplements such as Seachem's Excel. Plant tanks seem happy from 15-30+ppm CO2, depending on light, etc., but well above atmospheric equilibrium.