Does Vodak dosing work in FW??

[SDguy]

That's correct. The nitrifying bacteria that use ammonia and nitrite aren't limited by lack of organic carbon. If they were, you'd have elevated levels of either, or both.

Denitrifying bacteria (convert nitrate to nitrogen gas) are limited due to lack of low O2 areas, not organic carbon. This is why people often see high nitrates. Again, adding carbon won't increase their population.

I came across this article... quite interesting:
http://www.oscarfish.com/article-hom...-bacteria.html

[drainbamage]

Couple random thoughts, though it largely depends on your setup...

Foam fractioning can work in a heavily bio-loaded system, e.g. cichlid (either continent) or goldfish tanks/system. It would be possible to utilize a skimmer designed for FW use, using wooden airstones or a fairly large needle-wheel style pump, tall and skinnier than SW use cylinder for the mixing chamber, and have a foam fractioner for your tank, providing it's on the dirty side. If you were able to make something like that work, then yes, the vodka dosing could actually help, but it'd all be straight out experimental, so if you're just looking for an extra tweek of goodness, I wouldn't do it.

What sort of FW setup? you said plants would get torn to shreds so I'm figuring you have Africans, which leads to a whole potential of stuff IMO. If you have a heavy stacked rock tank, if you provided extra flow you would be able to utilize all that rock in similar fashion to SW live rock for bactera colonization and actually eliminate some of your filters on the tank. Advantage of eliminated filters is that if you don't keep them clean a LOT, especially with messy eaters, you end up trapping debris just like a filter sock and then actually forcing it to break down into 'trates through the whole process.

Random thoughts, always meant to try a "live rock" cichlid tank, but can't ever get myself to go back to FW, not even for tropheus.

[iVgOnMaD]

Well, its actually for my turtle tank as long as there is no ammonia im happy, they get 100% water changes every week, hoping I could make it into a 2 week cycle instead.

Thinking I might use a moded G1 skimmer I have and see how it works in freshwater, I can adjust the water level in the skimmer so I think I can make it work. Thinking it might only foam up for a limited amount of time while it removes the organics and will probably not foam while the water is clean. What do you guys think. Do you think it will be weird and overfill after feedings (foam up too much?)?

[drainbamage]

yea, you'd want a stable setup to really get the most benefit-with turtles you have sort of filthy water punctuated with really nasty water (not meant a slight to you, just saying turtles=messy both from the front and the back end.)

Worth a try, but I'm guessing the skimmer won't be able to run stable, so you'll be messing with the skimmer constantly instead of actually getting much out of it

[SDguy]

Oh man, turtles... I'd stick to massive water changes and canister filters. Furthermore, I would hate to promote non-specific bacterial growth in a turtle tank. It very well will grow on the turtles too... not a good thing.

[iVgOnMaD]

What do you think those "organic waste remover" for turtles are? Thinking it might just be a carbon source too, or what else can do that?

[laffingcrow]

There is another option not mentioned here yet... if you are a DIYer.
Algae Turf Scrubber also works for fresh water tanks.
Algae only removes nitrates and phosphates (fertilizer for algae)

If you're new to ATS... see "my tank" thread in my signature to start.
...also other ATS threads in DIY section.
two cents
Brian

[offroad537]

do water changes and cut down on the light. im have the same problem so im just cutting down the light. you might want to put good algea in your tank to take up what the bad algea would use. that might help.

[SoCalBoo]

I looked into foam fractioning/skimmer a year or so back, and everyone universally told me that it was not possible to generate the foam in FW. And by everyone I mean: wetwebmedia, reef central and local a few local LFS. I've never tried it, so I can't give you any data from experience - only what folks told me.

[iVgOnMaD]

Guess ill have to add salt, my turtles are actually native to brackish waters anyways

[drainbamage]

I looked into foam fractioning/skimmer a year or so back, and everyone universally told me that it was not possible to generate the foam in FW. And by everyone I mean: wetwebmedia, reef central and local a few local LFS. I've never tried it, so I can't give you any data from experience - only what folks told me.

Try it in some water from a turtle tank with a wooden airstone-you'll be really sorry you did after the smell hits ya

Edit: This may actually be a better bit of info: http://books.google.com/books?id=thk...atment&f=false

Basically the aquarium industry stole foam fractioners from the water treatment industry, which is predominantly freshwater in application. Big thing is that the nutrient concentration is WAY beyond what would conceivably be non-toxic in an aquarium capactiy.

Can't cite any sources, but when I did some research a few years back, the basics was that in the 70s 'skimmers' were popular, went out of fad, then came back with better technology. What's weird is I swear I read a lot of that info from a Fenner source.

[SoCalBoo]

interesting. I actually have a new set up leak testing right now. I'm gonna throw my skimmer on and see what happens...