Free calculators and tools for saltwater reef hobbyists. No account required.
Calculate your tank's water volume for rectangular, bow front, cylinder, hexagonal, L-shape, and corner pentagon shapes. Accounts for rock, sand, and equipment displacement.
Check if your water parameters are in the ideal range for reef, FOWLR, or freshwater tanks. Get actionable recommendations when levels are off.
Calculate exact dosing amounts for calcium, alkalinity, and magnesium supplements. Supports BRS, ESV, Brightwell, and generic products.
Calculate how much salt mix you need for water changes. Supports Red Sea, Instant Ocean, Fritz, Tropic Marin, and more.
Estimate reef tank startup and monthly costs for equipment, livestock, supplies, and electricity by tank size.
Estimate monthly and annual reef tank power consumption from lights, heater, pumps, skimmer, and chiller wattage at your kWh rate.
Pick the right protein skimmer rating for your reef tank based on water volume, bioload, and stocking style. Includes recommended skimmer type.
Calculate ideal flow rate (GPH turnover) for your reef tank from volume and coral type. Get powerhead count, per-powerhead GPH, and placement guidance.
Build a reef LED schedule with ramp-up, peak, ramp-down, PAR targets, channel suggestions, moonlight timing, and coral acclimation guidance.
Calculate the right heater wattage for your reef or freshwater aquarium from tank volume, ambient temp, and target temp. Includes dual-heater redundancy advice.
Check compatibility between 36 common reef fish species. See aggression level, reef-safe status, tank-size minimums, and pair-specific warnings.
Estimate safe aquarium stocking based on tank volume, filtration, and 36 common saltwater fish species. Includes compatibility and minimum tank warnings.
Identify and treat 12 common reef tank algae - GHA, bryopsis, cyano, dinos, and more. Visual guide with causes and treatment steps.
Identify 30+ reef aquarium corals - LPS, SPS, soft corals, and anemones. Filter by type, difficulty, and lighting; see care needs at a glance.
These tools give you a snapshot. My Reef Log gives you the full picture - log water tests, track trends, manage livestock, and stay on top of maintenance.
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