The definition of ‘low-tech’ tank was first published by Diane Walstad in her book “Ecology of the planted aquarium
It seems like the term showed up in the mid ‘90s in the news groups as a counteraction to the expensive tank setups from Amano and some Aquarium outfitter. People have been running tanks without those equipment successful for year. But of cause CO2 is the number one limiting factor in a tank.
After a blackout this winter I lost all my fish in my 3 year old planted tank. Finding a new balance for my tank I stumbled across Diane’s book. Very interesting scientific read. (it is only a text book, no pretty pictures!). All her findings are underlined with scientific prove.
Her main definition points for a low-tech tank are:
- 50% water change every half year
- A regular top soil as substrate
- Low light <2wpg, tank in sun light is fine too!
- Heavily planted
- No additional fert, all fertilizer are getting supplied by fish food (does mean feeding more than the fish needs)
- Slow moving filter, minimal biological filtration required. Plants taking care of biologic filtration
- A good bio-load
I only can recommend to have read in this book just to understand the underlying principles in our little eco systems. Injecting CO2 and additional fertilizer results in a high-tech tank aka frequent maintenance.
I started my tank (50gal) as a DIY high tech tank 3 years ago with CO2, ferts and 2 wpg and over the time it became a low tech tank due to lack of interest in performing regular maintenance. Only during the initial setup I have to fight with algae. Since now I only lost one Sword plant and some vals. The tank is still heavy planted with Anubias (wich has some black algae), sword, vals and java fern. The only algae eater in it was a common pleco, accommodated by 3 Pearl Gourami, 3 Emperor Tetra, 4 Madagascar Rainbowfish. For at least 2 years maintenance was a 25% water change every 3-4 months, filter cleaning ones a year(I could have turn it off) and feeding the fish and I never had a test kit. Plant grow went down to 1/10 of the initial setup, but the tank was already grown in. Since the lost of all fish during the blackout the tank came out of balance and I got a algae bloom. I’m still trying to get the balance back… During the entire time the tank was always nice to look at for my taste.