Dive Deeper: Choosing a Reef Tank Dosing Pump
Stability beats perfection in a reef tank. Corals tolerate an alkalinity of 8.2 dKH held steady far better than an 8.8 that swings to 7.4 and back every time you dose by hand. An aquarium dosing pump is the cheapest way to buy that stability: it splits your daily demand into a dozen or more micro-doses spread across 24 hours, which is much closer to how a reef consumes elements in the wild.
How Many Channels Do You Need?
One channel. You are running an all-in-one additive like Tropic Marin All-For-Reef or a single alkalinity supplement. Simplest possible setup, lowest cost, and enough for most tanks under 50 gallons with light coral load.
Two channels. The classic calcium and alkalinity pair. Never dose these into the same spot at the same time — stagger them by at least 30 minutes and dose into high-flow areas on opposite sides of the sump.
Three to four channels. Calcium, alkalinity, magnesium and one trace or amino supplement. This is where most SPS-dominant tanks land, and where four-head systems like the ReefDose 4 and Versa 4-pack pay for themselves.
Continuous-duty pumps. Calcium reactor effluent, kalkwasser top-off, and automatic water changes need a pump that runs for minutes or hours, not seconds. That is a different pump class from a micro-doser — look at the Hydros Sole and similar continuous-duty units.
Sizing the Dose to Your Tank
Start by measuring consumption, not by copying someone else's schedule. Test alkalinity at the same time on two consecutive days with no dosing in between. The drop is your 24-hour demand. Dose to replace exactly that, then re-test after three days and adjust. As corals grow, demand climbs — expect to increase your dose every few weeks in a growing SPS system.
Installation That Prevents Problems
- Mount the pump above the reservoir and above the waterline. This prevents siphoning if a check valve fails.
- Use rigid tubing on the discharge side and secure it so the line cannot fall into the sump.
- Dose into high flow, ideally the return chamber or in front of a powerhead, so the additive disperses before it contacts coral tissue.
- Label every line and reservoir. Dosing calcium into the alkalinity container is a tank-ending mistake, and it happens more often than anyone admits.
- Keep reservoirs covered to stop evaporation from concentrating your solutions over time.
Calibration and Maintenance
Peristaltic tubing stretches. A pump calibrated to deliver 1.0 mL per second when new may deliver 0.85 mL after six months, which silently under-doses your tank. Re-calibrate with a graduated cylinder every three months, replace dosing tubing annually, and inspect the head for salt creep or crystallized additive at every water change.
Brands We Carry
EcoTech Marine Versa — quiet, app-controlled, and expandable through a shared base station.
Neptune Systems DOS — dual-head precision dosing that integrates directly with an Apex controller for automated water changes.
Red Sea ReefDose — two- and four-channel dosers with a built-in display and self-calibration.
Kamoer — WiFi and Bluetooth dosers including the FX-STP series, a strong value option for multi-channel setups.
Hydros — Sole continuous-duty dosing and Blenny four-head micro-dosing that ties into the Hydros controller ecosystem.
Pair Dosing With Testing and Control
Every dosing adjustment should be verified. Confirm results with aquarium water test kits, automate the schedule with an aquarium controller, and stock the additives themselves from our reef supplements and water chemistry range.
