Reference table
Ideal water parameters. For every tank type.
Saltwater reef. FOWLR. Freshwater community. Planted. African cichlid. Discus. Shrimp. Brackish. Koi pond. The targets, the safe ranges, and what each parameter actually controls. Bookmark this page.
Saltwater reef (mixed reef, SPS-dominant, LPS-dominant)
| Parameter | Mixed reef | SPS-dominant | LPS / soft |
|---|
| Temperature (°F) | 76-79 | 76-78 | 76-80 |
| Salinity (sg) | 1.025-1.026 | 1.025-1.026 | 1.024-1.026 |
| pH | 7.9-8.4 | 8.0-8.4 | 7.9-8.4 |
| Alkalinity (dKH) | 8-9 | 7.5-8.5 (stable) | 8-10 |
| Calcium (ppm) | 420-440 | 420-450 | 400-450 |
| Magnesium (ppm) | 1300-1400 | 1300-1400 | 1300-1400 |
| Ammonia / nitrite | 0 | 0 | 0 |
| Nitrate (ppm) | 1-10 | 1-5 | 5-25 |
| Phosphate (ppm) | 0.02-0.10 | 0.02-0.05 | 0.05-0.15 |
Stability is more important than the exact target - alkalinity swings of 0.5+ dKH/day cause STN and tissue recession in SPS faster than slightly off-target stable values.
Saltwater FOWLR (fish only with live rock)
| Parameter | Range |
|---|
| Temperature | 76-80°F |
| Salinity | 1.020-1.025 sg (lower than reef OK) |
| pH | 7.8-8.4 |
| Ammonia / nitrite | 0 |
| Nitrate | under 30 ppm |
Freshwater community
| Parameter | Range |
|---|
| Temperature | 74-80°F |
| pH | 6.8-7.6 |
| GH (general hardness) | 4-12 dGH |
| KH (carbonate hardness) | 3-10 dKH |
| Ammonia / nitrite | 0 |
| Nitrate | under 40 ppm (under 20 with sensitive species) |
Planted tank (high-tech CO2)
| Parameter | Range |
|---|
| Temperature | 72-78°F |
| pH | 6.4-7.0 (with CO2 injection) |
| KH | 2-5 dKH |
| CO2 (ppm) | 20-30 |
| Nitrate | 10-25 ppm (target via fertilization) |
| Phosphate | 0.5-2 ppm |
| Iron | 0.05-0.10 ppm |
African cichlid (Lake Malawi / Tanganyika)
| Parameter | Malawi | Tanganyika |
|---|
| Temperature | 76-82°F | 76-80°F |
| pH | 7.8-8.6 | 8.0-9.0 |
| GH | 10-18 dGH | 12-20 dGH |
| KH | 10-15 dKH | 12-18 dKH |
Discus
| Parameter | Range |
|---|
| Temperature | 82-86°F |
| pH | 5.5-7.0 (lower for wild, higher for captive) |
| GH | 1-8 dGH |
| KH | 1-4 dKH |
| Nitrate | under 20 ppm |
Shrimp tank
| Parameter | Neocaridina | Caridina (CRS / Taiwan Bee) |
|---|
| Temperature | 68-78°F | 68-74°F |
| pH | 6.5-8.0 | 5.5-6.5 |
| TDS | 200-300 | 100-180 |
| GH | 6-12 dGH | 4-6 dGH |
| KH | 2-8 dKH | 0-2 dKH |
| Ammonia / nitrite / nitrate | 0 / 0 / under 20 | 0 / 0 / under 10 |
Brackish & koi pond
| Parameter | Brackish (1.005-1.015 sg) | Koi pond |
|---|
| Temperature | 74-82°F | 50-78°F (seasonal) |
| pH | 7.5-8.4 | 7.0-8.5 |
| Ammonia / nitrite | 0 | 0 |
| Nitrate | under 30 ppm | under 50 ppm |
| KH | 5-10 dKH | 5-12 dKH |
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