The short answer
Bubble Magus Curve 5 is the budget sump benchmark. Tunze 9004 solves the no-sump problem. Nyos Quantum 120 is the compact premium AC route. Red Sea REEFER DC 300 makes most sense when its controller cost or ReefBeat ecosystem is already justified. Deltec 600i is the premium serviceability shortlist—but verify which generation a retailer is actually selling.
| Model / checked price | Format / fit | Published performance | Reef Bench decision |
|---|---|---|---|
| Bubble Magus Curve 5 £110–£125 | In-sump AC 185 × 180 × 470mm; 241–279mm water | 8W; 300l/h air listed | Budget sump route; published ratings conflict between 300 and 700L, so do not size from the highest claim |
| Tunze Comline 9004 £148–£170 | In-display / rear section 110 × 90 × 305mm; 225–245mm immersion | 4W; 150l/h air | Best route here when there is no sump; maker says 60–250L depending on load |
| Nyos Quantum 120 £300–£320 | In-sump AC 150 × 210 × 465mm; about 210mm water | 8W listed | Compact premium sump option; up-to-500L claim still needs load margin |
| Red Sea REEFER DC 300 £349 skimmer; about £499 with controller bundle | In-sump DC + app controller Two footprint orientations; 530mm high; 160–200mm water | 20W; 500l/h air | Strong control and overflow-management route; controller requirement changes real price |
| Deltec 600i / SC-Pro 600i £431–£473 | In-sump DC Check exact 600i generation before ordering | Adjustable 24V DC | Premium serviceability and overflow-safety route; retailer naming/specification varies |
The rating problem
The Curve 5 is a useful warning: current UK listings describe anything from 300–500 litres to 500–700 litres for the same basic model. Red Sea instead publishes separate SPS, mixed-reef and fish-only ratings. These figures should not be placed in one “capacity” column as though they mean the same thing.
Electricity is not the biggest cost
At 26.11p/kWh and continuous operation, 4W is roughly £9 a year, 8W about £18 and 20W about £46. Purchase price, controller, replacement pump, cleaning access and the chance of buying twice usually matter more. Model your tariff in the electricity calculator.
Sources and limitations
Specifications were checked against Tunze and Red Sea, plus current UK distributor and retailer listings for Bubble Magus, Nyos and Deltec. Price evidence included Complete Aquatics, Finest Aquatics, Porton Aquapet, Marine World Aquatics and Perfect Aquatics. We have not independently measured noise, air draw, skimmate production or long-term reliability.