Nutrient Pressure
Bioload relative to the water in your system. Not a water-quality reading — a structural estimate of how hard your filtration is working.
Fish — 19.0🐟 Firefish Goby ×2 (1.5×2)
🐡 Ocellaris Clownfish ×2 (2.0×2)
🐟 Orchid Dottyback (2.0)
🐟 Royal Gramma (2.0)
🐟 Six Line Wrasse (2.5)
🐟 Tailspot Blenny (1.5)
🐟 Yellow Tang (4.0)
Coral & Inverts — -1.2🦐 Skunk Cleaner Shrimp ×2 (0.2×2)
🪸 Duncan Coral (0.0)
🪸 Hammer Coral (0.0)
🦀 Blue Leg Hermit Crab ×8 (-0.1×8)
🪸 Acropora SPS (-0.2)
🪸 Torch Coral (0.0)
🐚 Turbo Snail ×3 (-0.2×3)
Total bioload score: 17.8
1 hitchhiker not counted (arrived on rock/frag — tracked, but not stocking you chose)
Skimmer: 200 gal rated → 120 gal effective (60% real-world factor)
Estimate only — does not account for live rock, DSB, carbon dosing, water change frequency, or coral uptake.
Formula: score = (total bioload ÷ water volume) × 150, capped at 100
Bioload scores are per-animal estimates of relative nutrient output. Fish are the primary drivers. Corals and inverts contribute a smaller fraction. Each animal's score is multiplied by its quantity.
Water volume is the water actually in the system, not the size of the glass. From the sizes in Settings → Tank Setup we assume:
- Display: 20% less for rock and sand, which take up roughly a fifth of a typical reef display.
- Sump: 50% full. A sump runs well below its rim so it can hold the water that drains down when the return pump stops.
- Refugium: counted full.
So a 100-gallon display with a 50-gallon sump counts as about 105 gallons of water. More water dilutes bioload and lowers the score.
Why ×150: it is a scale, not a measurement. It turns bioload per gallon into 0–100 so that about 0.23 per gallon is the top of “Well managed” (35) and about 0.67 per gallon reads 100.
Skimmer and refugium data is shown in the breakdown above for reference but does not currently modify the score — the score is pure stocking density. This keeps it honest: filtration helps, but can't compensate for being genuinely overstocked.
- Live rock and DSB biological filtration capacity
- Water change frequency and volume
- Carbon dosing (vodka, vinegar, NoPox, etc.)
- Coral nutrient uptake (SPS tanks can run higher bioload)
- Feeding volume and food type
- Flow rate and skimmer real-world performance
Use this as a structural gut-check, not a substitute for regular water testing. Your actual nitrate and phosphate readings are the ground truth.
thanks — we read every one