Dimensions 51 × 25 × 30 cm

Title Seeking Sustainability

Volume 38L

Background Deep Blue Sea background

Lighting 1x15W PowerGlo tube, 1x10W GE soft white compact fluorescent

Filtration Undergravel

Plants Shinnersia rivularis (Mexican oak leaf);
Althernantera reineckii;
Aponogeton crispus;
Didiplis diandra;
Vesicularia dubyana (Java Moss);
Echinodorus cordifolius;
Valisneria spiralis & V. americana;
Bacopa monnieri (Moneywort);
Microsorium pteropus (Java fern);
Anubias barteri var. nana;
Ceratophyllum demersum (Hornwort);
Cryptocoryne wendtii;
Eleocharis sp. (hairgrass)

Animals 1 x Epalzeorhynchos frenatum (Rainbow shark);
6 x Paracheirodon innesi (Neon tetra);
3 x Xiphophorus maculatus (Mickey Mouse platy);
3 x Corydoras schwartzi (Striped Cory catfish);
3 x Otocinclus affinis (Dwarf Otocinclus);
Ghost shrimp;
Ramshorn snails;
Melanoides tubercularia (Malaysian trumpet snails)

Materials We use regular (approx. 3 mm) aquarium gravel. Additional elements are 3 pieces of driftwood, rocks and pebbles, and a few shells.

Additional Information Early on we decided that the long-term stability of this little tank required that we keep plant growth slow. We do not inject CO2, did not fertilize the substrate, and use liquid fertilizer (Flourish) sparingly. Plant growth is conveniently slow as a result. The water's CO2 content is low (around 3 ppm, pH ~ 7.4, KH = 3), suggesting that CO2 is the limiting factor for plant growth.
Despite the apparent CO2 limitation some plants do grow profusely, such as the hornwort. Aside from a 20% water change every 2 weeks we mostly remove nitrogen and phosphorus by pruning the hornwort. Also, our conservative use of fertilizer + our cleanup crew keeps most algae away. We occasionally need to remove green filamentous algae, but never had to clean the glass in the 8 months the tank has been going. The tradeoff from our snail army is their occasional nibbling on the plants, but we think it gives the tank a natural look.

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