PAR / PUR maps · multi-fixture layouts · saltwater refraction
Fixtures
Custom Fixture Editor
I0 scales overall PAR. Higher beamN = tighter hotspot (like Phantom). Higher soft = flatter edges (like Radion). Changes apply live when this custom is selected.
Tank & optics
Counts per type (0–4). Total units placed evenly.
Combo layout
Click a unit, then click the heatmap to drop it. X is along tank length, Y is across width. Each unit can have its own 0°/90° rotation.
Output & view
Select fixtures to compare
Independent comparison uses current hang height, tank size, dimming & measure depth (1× count each). When “combined” is checked, the heatmap shows all selected fixtures placed together and summed.
Phantom Pro ×3
Top view @ measure depth
X / Y sliders move the selected manual fixture on the mapY ↑ width · X → length
020040060080010001200+ µmol PAR/m²/s
Salinity 34.5 ppt → n ≈ 1.339. Water column optical path adjusted. Column transmits ~88% (surface + absorption). Profiles are radially-symmetric approximations fitted to published aggregates / manufacturer claims. Not laboratory measurements.
What the numbers mean
PAR / PPFD = µmol photons m⁻² s⁻¹ (400–700 nm).
PUR = Photosynthetically Usable Radiation ≈ PAR × spectrum weight for coral chlorophyll / accessory pigments.
DLI = Daily Light Integral (mol m⁻² day⁻¹) = avg × photoperiod × 0.0036.
Target green band for SPS ~10–16 mol/day is common.
Evenness = 1 − (max−min)/avg (higher is flatter).
Price/PAR uses street prices (editable conceptually): Phantom ~$1099, Radion G6 ~$900, Straton X ~$1000.
Refraction shortens the effective optical path in water (n≈1.34). Walls add a simple diffuse bounce term.