converting tank to El Natural

Question
Hi, thanks for your time,
So you have probably heard about the "El Natural" method of aquarium
keeping, where one uses potting soil under the gravel and live plants as a
sort of ecosystem negating the need for filters and tank changes.

I have a couple of tanks and I am about to move one setup from a 10 gallon
to a 30 gallon.  I am interested in trying out the "El Natural" method and this
seems like a good opportunity.  

The livestock in this tank are zebra danios, cherry shrimp, hillstream loach,
snails, and two fire bellied newts.

The tank is/will continue to be heavily planted with a lawn of glossostigma
and several other plants.  In the new setup I intend to include some ponds
plants, papyrus and lotus, and make a small island with moss and ferns for
the newts to climb out on.

I would love your thoughts on how best to do this and what to watch out for,
but my main question is: can I go without a filter?  

I have left the filter unplugged for a week every once in a while and the
activity in the tank from all species picks up, so I think they prefer it, but I
worry they may all of a sudden drop dead.

Thanks

Answer
That sounds like a wonderful project!

However, as much as I have wanted to do something similar to your idea, I've never had the opportunity to do such. So I don't feel like the best one to offer advice about it.

However,

You might want to check out some of these articles about natural planted tanks.

The "Walstad method" is quite interesting...

http://thegab.org/Articles/WalstadTank.html

http://thegab.org/Articles/PottedPlants.html

That should give you some ideas and I'd love to hear updates on your project if you like. ;-)

Hope this helps!
Karen~