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What are the HMC-500S capacity and element length?
Finnex specifies 500 W, 100–125 US gallons and a 15.1-inch element for HMC-500S. The listing’s lower endpoint is not optional; the current matcher cannot enforce 100 gallons, so it remains reference-only.
Explore this need in the finder →Which temperature setting range is stated for the HMC-500S?
Finnex lists 68–92°F and describes an external adjustable digital controller, separate remote sensor and stored setting after power interruption. The page does not give a measured accuracy/tolerance result.
Explore this need in the finder →Does Finnex describe HMC-500S for marine water?
The official HMC family page describes the titanium HMC series for marine and freshwater environments. That is a manufacturer suitability statement, not a substitute for the exact package instructions or the full electrical input rating.
Explore this need in the finder →The upper HMC size is rated to 125 gallons
Finnex lists HMC-500S as a 500 W titanium heater for 100–125 US gallons, with a 15.1-inch tube and 4.17 A at the table’s 110 V reference. The manufacturer’s table gives the HMC family a 68–92°F adjustment range. HMC-500S is the highest wattage in the six-row HMC family table; the source does not list a larger HMC model or a tank-volume band above 125 gallons. Do not extend the 500 W entry to a larger aquarium just because the heater is the biggest in this series.
The 100-gallon minimum is also essential. This row meets HMC-400S at 100 gallons, but the family page assigns 400 and 500 W models distinct bands, and the equality at one endpoint does not prove that output, recovery, spatial fit or thermal behavior is the same.
Remote control and safety language
The HMC product description includes an illuminated digital control unit, adjustments, a separate temperature sensor and memory for the last setting after a power interruption. Finnex describes the sensor as being positioned apart from the heat source and says the heater resumes operation at the stored setting. These are manufacturer claims, not results from a temperature test or outage simulation. The 68–92°F control range should not be mistaken for an appropriate temperature for a particular species; use separate animal-care guidance and measure the aquarium water independently.
The HMC uses a titanium element and a flame-retardant guard, and the manufacturer page describes the family for freshwater and marine environments as well as submersible. The inspected instructions index has no HMC manual entry, and the pages do not show the exact waterline, mounting position, immersion depth, orientation or clearances. A guard can reduce direct contact but does not remove the need for a safe installation. Titanium should not be represented as a tested guarantee against every kind of breakage or failure.
Shop identity and remaining checks
The current Finnex Shop record includes a distinct 500 W option with SKU HMC-500S and its own Shopify variant ID. The barcode is null. The same grouped product record contains 100, 200 and 300 W options; 50 and 400 W appear on the family table but not in this Shop option set. This is useful for distinguishing the exact model from a generic listing, but it does not establish current stock, independent retailers’ inventory or an exact package.
The gallery is shared among four Shop variants and uses HMU-named assets. The files show no 500 W label or HMC-500S package, so none is integrated as this exact heater image. The 4.17 A specification is referenced at 110 V; full input voltage range and frequency remain unknown. Check the actual unit’s label and instructions rather than assuming that one amperage value is the complete supply rating.
Why this high-capacity configuration is reference-only
A 100-gallon lower boundary cannot be represented by the existing finder. A maximum-only rule would accept the HMC-500S below 100 gallons, contradicting Finnex’s own table. For that reason this review is not presented as a product match and there is no fixed purchase landing for it, despite the documented Shop SKU. The current evidence also lacks complete electrical and installation details, and the exact wattage image is unresolved.
The HMC-400S shares the 15.1-inch tube length but has a different 80–100-gallon row and no verified Shop option. The HMC-300S is a separate 60–80-gallon configuration. Compare those source records only as documentary alternatives, not as a tested ranking. Confirm actual water volume, room conditions, livestock needs, model identity and installation instructions before purchase or setup.
Key specifications
Key details at a glance
| Rated heater power | 500 W |
|---|---|
| Lowest thermostat setting | 68°F |
| Highest thermostat setting | 92°F |
| Temperature control | Adjustable thermostat |
| Supported water types | freshwater / saltwater |
| Installation route | Fully submerged, in-tank |
Use the exact model’s instructions for operating limits, supplied equipment and version differences.
Sources for this review
Sources for this assessment
Check the complete aquarium setup
Use the finder to compare documented tank size, water type, installation and temperature-control fit. A match does not guarantee the keeper's species-specific target or measured performance.