Each parameter is normalized to its ideal range — 0% = low end, 100% = high end. Hover for actual values.
Bridge readings older than 24 hours are summarized at 5-minute, 1-hour, and daily intervals to keep the chart fast. Manual entries are kept as-is; after your last manual reading the line carries forward dashed to today. Learn more
🧪This is the #1 parameter that kills corals when it swings. Think of it as the skeleton-building ingredient. Dose consistently and test every day if you have SPS.
Calcium
Ca²⁺
380-450
350-500 ppm
~400 ppm
ppm
🦴Calcium is literally what coral skeletons are made of. 420-440 ppm is the sweet spot — not too low (slow growth) or too high (chemistry gets weird).
Magnesium
Mg²⁺
1200-1400
1150-1450 ppm
~1285 ppm
ppm
🔗Magnesium is the chemistry glue — it keeps calcium and alkalinity from fighting each other. Low mag = parameters that won't stay stable no matter what you dose.
Salinity
1.025-1.026
1.022-1.028 sg
1.025-1.027
sg
🧂Match the real ocean exactly — 1.025 SG. Your fish evolved for this. Even small swings stress them out. An ATO keeps it rock steady.
Temperature
75.9-80.0
74.0-82.0 °F
77-84°F
°F
🌡️Keep it like a warm beach day — 78°F is the sweet spot. Too cold and fish get sluggish. Too hot and oxygen drops fast.
pH
8.1-8.4
7.8-8.4
8.0-8.3
⚗️The ocean is slightly basic, and your tank should be too. pH naturally drops at night — open a window or run a refugium on a reverse cycle to keep it up.
Nitrate
NO₃⁻
1.0-10.0
1.0-20.0 ppm
~1-5 ppm
ppm
🌿A little nitrate is actually good — corals and algae need it as food. The danger zone is above 20 ppm where nuisance algae explodes. Aim for 5-10 ppm.
Phosphate
PO₄³⁻
0.01-0.03
0.01-0.1 ppm
~0.03 ppm
ppm
🎨Corals need tiny amounts of phosphate to look colorful. Zero phosphate = pale, stressed corals. Too much = algae takeover. 0.05-0.08 ppm is the sweet spot.
Nitrite
NO₂⁻
0.0-0.1
0.0-0.5 ppm
~0 ppm
ppm
⚠️Nitrite is the middle step in the nitrogen cycle — toxic to fish gills. Should be zero in an established tank. If it spikes, something died or your cycle isn't done.
Ammonia
NH₃
0.0-0.02
0.0-0.1 ppm
~0 ppm
ppm
☠️The most dangerous parameter. Even 0.25 ppm can kill fish within hours. Zero always. If you see any ammonia in an established tank, do a water change immediately.
ORP
250.0-400.0
200-450 mV
~400 mV
mV
⚡Oxidation reduction potential — a real-time proxy for water cleanliness. Healthy reef tanks sit 250–400 mV; lower hints at organic load building up (skimmer, GAC, water change). Probe drift is common; recalibrate quarterly.
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