Glossary
ULNS
/U-L-N-S/
Ultra-Low-Nutrient System. NO₃ < 1 ppm, PO₄ < 0.02 ppm.
An approach to reefkeeping that targets very low nutrients via heavy skimming + carbon dosing + GFO. Produces saturated SPS colors but is dinoflagellate-prone if pushed too far. Triton Method is the most popular ULNS framework.
Recommended
For dialing in low-nutrient tanks without crashing into dino territory.
Hanna Phosphate Checker (HI-774)
Low-range phosphate, essential for ULNS tanks.
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Brightwell NeoNitro nitrate supplement
Adds nitrate to ULNS tanks fighting dinos.
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Brightwell NeoPhos phosphate supplement
Adds phosphate to ULNS tanks fighting dinos.
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