At the risk of spamming this on every fish forum going I thought I'd a post a bit about my largely self sufficient aquarium, as this seems to get discussed on here a fair amount.
As a bit of background, I set this up because I'm frequently away from home for 5-6 weeks at a time, and wanted an aquarium I could just leave on it's own for this length of time. As such it is entirely pragmatic and practical in it's design, and is not intended as a closed system, biotope 'simulation' or whatever.
Neither is this particualary new or innovative, pretty much all the ideas were stolen from somewhere or other. However, it does all work, so might be of interest to anyone considering a similar setup.
3'x1'x3' 10mm glass aquarium, open topped
70W metal halide light 2 feet above water surface (8 hours/day)
Small, heavily throttled powerhead providing very slow water movement to help prevent surface biofilm
John Innes compost (unmineralised) cut 50/50 with sand, with pure sand cap
Some rocks, and locally collected heather twigs
Echindorus, water pickerel
Riparian plants ('foliage' houseplants from DIY shops):
Prayer plant, parlour palm, peace lillies, unidentified lillies. Planted in shower caddies using hydroton as a substrate.
Swords, crypts, mosses, hydrocotyle, Micranthemum micranthemoides, water lillies, other low-medium light plants, various floating plants.
6 Parosphromenus sp. 'sentang'
, 7 Bororas maculata
, 4 otos, cherry shrimp, assorted snails, ostracods and other inverts.
Maintenance and feeding:
I normally just top off the water lost to evaporation with dechlorinated tap water and add beech/oak/ketapang leaves for the inverts to feed on. Roughly every couple of months I'll do a small water change, and sometimes supplement the food with the odd algae wafer.
Once everything was planted I waited about a month for the plants to adapt (the riparian plants required a few weeks to grow new root systems) and for the initial ammonia spike to pass then added about 50 shrimp, the otos and a few other inverts - lots had arrived already on the aquatic plants. Once the shrimp population was looking good (about 3 months in) I added the rasboras, then the gouramis after another month or so when I was sure the food chain was stable.
Tank is now 10 months old and doesn't require any more maintenance than topping up the water and replacing the beech, oak and ketapang leaves as they are broken down. I do do a small water change every couple of months and supplement the feeding a bit when I happen to be home, but I don't feel it's essential.
The gouramis and rasboras seem to find plenty to eat in the tank (ostracods and baby shrimp are the main food items I think), and the otos always have bellies that I would describe as moderately rounded.
var. "red" (female):