From The Aquarium Wiki
What is it?
ULNS is an acronym for Ultra Low Nutrient System.
It applies to various methods of growing reef SPS corals to provide stunning colours and growth by using micro-nutrients, chemicals and bacteria to keep corals natural toxics at a ultra low level..
This is a collection of absorbing chemicals (zeolites) and bacteria for dosing into a reef aquarium with corals to achieve a ultra low level of nitrate and phosphate. The bacteria consume uneaten food and nitrate and the zeolite absorbs phosphate and ammonia therefore providing an enriched and healthier environment for the animals.
- See example of products - Reefstock - Zeovit
A system of bacteria (probiotics), for example, Bioptim to reduce nitrate and phosphate to low levels in a reef aquarium.
Balling (Light) method
Named after Hans-Werner Balling and said to be the most common used supplementation method for reef aquariums in the EU.
Chemicals like Calcium, Carbonates, Magnesium and other trace elements are constantly replenished as they are taken up by the coral.