Freshwater protein skimming?

[chorrylan]

I'm in the early stages of thinking about going over to the dark reefy side for one tank so was thinking about purchasing a protein skimmer as one of the first steps... and during the long gestation period..... trying it out on some freshwater tanks.

With water changes being a slow, painful, wasteful and potentially very cold process for my fish the prospect of stretching water-change cycles even a little bit though removal of some of the waste early in the nitrogen cycle sounds tempting (with some real luck I mght even get my waterchange cycles as long as this sentence :-) )

Anyhow.... I can see info around about commercial grade protein skimmers being used with freshwater but not hobbyist equipment.

So I'd like to hear from people who have actually tried (or seen other people trying) protein skimmers in freshwater tanks and their success or otherwise.

if you've tried it then please post up what particular brand, model and size unit you used and the degree of success or failure. Apart from being interested in people who have succeeded I'm also interested in people who had it "nearly" work or have suggestions about what it might take to get this to work (hmmm like perhaps a drip feed of melafix into the system).

[Ash]

Do you already have denitrification going on? might be easier to get working is all

I have to admit I'm curious about freshwater skimming too but nothing has ever been anything more than rumours as far as I've read

[AzFish]

I looked into this awhile ago and gave up on the idea.

From what I have read in the past FW skimming is not really that possible due to the fact FW is not 'dense' enough .. Good skimming requires minute bubbles for it to work effectively, something that will be hard replicate in a FW set up ..

You could try a beckett injector that 'may' give you bubbles small enough to do the trick, otherwise I'd go with what Ash said, denitrification filter.

[chorrylan]

Do you already have denitrification going on?

ummm... I try :-)

I have some tanks setup with plenums but no real way to tell what effect they have other than that I still have higher nitrate levels than I'd like.

I have a DIY multi-coil+matrix setup still cycling (a test today comparing inflo vs ouflow show it's still producing nitrite but nitrates are dropping about 20ppm.

I have a plain DIY coil on one tank that has only been there a week so is just producing nitrite at the moment.

[Ash]

I ditched the coils & went with a slow flow denitrate filter like CThompson uses, cause the coils were getting clogged too easily (no prefilters, my bad) and it seemed too easy to break the cycle in them as well.

[Tunnel Rat]

slow flow denitrate filter like CThompson

please tell me more

Rat

[fishdance]

I have used both protein skimmers and denitrification coils on freshwater. Both are possible but I switched to a constant drip water change for almost all my tanks and havent used either for years.

I used a Berlin skimmer with powerhead and although it is not as effective as salt water, it did extract a lot of protein. The denitration coil was simply a long 50mm coil of 4mm black micro irrigation tube with as slow a flow rate as I could get. A couple of drips per minute and I put the output into the trickle chamber to re-oxygenate and in case any sulphides. I never measured its effectiveness but it was easy and cheap to do.

Some commercial marine fish collectors I know use plenums on their own saltwater fishtanks. It definitely works on salt so it should(?) on fresh. Their substrates are really thick though, sometimes over half the tank depth is substrate since they use a mesh barrier to stop organisms turning it over. I run bare bottom tanks so Ive never tried plenums on freshwater.

[Ash]

slow flow denitrate filter like CThompson

please tell me more

Rat

I have mine teed off sumps with 4mm line running flat out - it worked out to 150lph & the max for denitrate is 250lph (from memory, check the seachem site)

1) get more than enough denitrate for your system, I have a bit over a kilo for a 4x2 (or was it by volume, as in a litre? )

2) put it in a sealed container (cheapskates use the one it comes in, I had a hard plastic jar, some use small cannister filters)

3) set it up so the water goes in one end & out the other (basically make a canister if you didn't use one - mine isn't perfectly sealed at the top so it sits in the sump)

4) get the flow below the reccommended limit (most canister filters flow way too much, so either restrict one to a suitable flow, tee off a sump return with a tap to control flowrate or use a smaller dedicated pump but remember head height)

5) wait for it to cycle (or cheat & dump in Seachem Stability, it says it has aerobic & anerobic bactera in it)

If you have an outlet hose you can collect the water & check its nitrate reading vs that of the tank as a whole

hope this helps

Cheers

Ash