[foxfish]

I was hoping we could discuss UGFs.
For many years it was made very clear though magazines & other literature that UGFs were of no of no use in a planted tank.
It was said UGFs would draw oxygen over the plant roots & stunt their growth. In fact I believe certain manufacturers of related plant growing equipment still print this though their advertising.

However it would seem that plenty of people have successfully used UGFs.....

Because I was always lead to believe UGFs would simply not allow my plants to survive, I have never tried using a UGF in a full on planted tank but I can see how they might be a benefit...

I would consider using a reverse flow system, pre filtered through a canister & then through a external reactor.

I would like to know if drawing Co2 enriched water up though the substrate would effect the plant roots?

I can see that this way the gas would be very evenly distributed & the water column would continuously fertilize the substrate.
Fox.
PS I did post this on an English based site but had very few replies

 

[lauraleellbp]

You might be interested to read through Hoppy's recent RUGF setup:

http://www.plantedtank.net/forums/diy/78505-rfug-blast-past-diy.html

IMO UGF/RUGFs are great biofilters, but don't have enough mechanical or chemical filtration options, need too much maintenance to keep them clean, and also can be clogged by plant roots. HOBs and Canisters offer me those options with easier maintenance, so those are always my own choice.

 

[Hoppy]

My RFUG works fine with plants, with no root clogging, no maintenance problems at all. The disadvantage of it is that I can't use substrate fertilizing with it, and I am limited to inert substrate materials. My experience with it was that introducing the CO2 through such a filter is much better in theory than in practice. I saw no difference in my BBA battles when I switched to this method.

 

[foxfish]

Thanks for the replys.
I do realise that if you flow o2 rich water through the substrate there will be little if any (depending on the structure of the substrate media) anaerobic activity but I am not sure if this matters?
I was thinking about a more open structure for the substrate like a porous baked clay (cat litter).
I do think that by feeding Co2 rich water up through the substrate (reverse flow UGF) would give a very even distribution of the C02 & offer a high turnover rate with out too much surface gas exchange.
Obversely this method would supply the roots, whether they need it or not, with all the fertilizers we feed into the water column.
I normally run sumps on my tanks & I could still run the sump return into the UGF base via a co2 reactor.
Not trying to be to clever or anything just wondering if it would be a worthwhile experiment?
I very rarely keep a display for more than a year anyway so I dont think clogging would be an issue.

 

[foxfish]

OK I have read through the link above - brilliant!
Hoppy you were obviously thinking ahead of me but I feel my sump might offer some benifits to the concept?
One thing with a sump, you can monitor the flow through the tank very accurately by simply measuring (timing) the return flow in a 1lt jug.
I think I would try & push quite a lot through the UGF but the water will be well filtered mechanically beforehand.
I think cat litter would seem to be a good substrate to try, the hard baked clay type that is.