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What tank range does Finnex assign to the TH-500S?
The TH-500S is the 500 W entry, with a published 70–130 US-gallon range. That overlaps the TH-300S's range at 70–80 gallons, so wattage alone does not make the 500 W model a universal upgrade. The lower boundary is real and cannot be enforced by the current maximum-only matcher; this remains a reference, not a shortlist result.
Explore this need in the finder →How much space does the TH-500S tube need?
Finnex's TH-family specification lists a 14-inch tube with a 0.75-inch diameter. That is longer than the 10-inch TH-300S but shorter than the 16.5-inch TH-800S. The number is tube length, not confirmed installed clearance or permission to mount it in any orientation; check the exact instructions and available tank space.
Explore this need in the finder →Is the 500 W TH-500S a thermostat-equipped heater?
The Finnex Shop calls the TH offer a titanium tube only and states that controllers are sold separately. Finnex describes TH tubes in a separate HC-820M Deluxe Combo and says three-prong-compatible controllers can be used, but a controller's temperature range is not built into the tube and should not be borrowed unless that separate controller is actually part of the package.
Explore this need in the finder →The middle TH configuration, not a universal step-up
This research-based review concerns the Finnex TH-500S, a 500 W titanium heating tube. It is not a hands-on report and does not claim independent heating, efficiency, longevity or temperature-accuracy results. Finnex's current TH/THD family table names TH-500S and lists 120 V, 4.5 A, a 0.75-inch diameter, 14-inch tube length and a 70–130 US-gallon band. The matching Shop selector offers 500 W as one of three TH tube wattages. Finnex's separate controller-combo table labels the corresponding bundled configuration TH-0500S, with the same wattage, 14-inch tube and 70–130-gallon range. The zero-padded code form is preserved as a combo-page naming difference, not an invented SKU.
Its rating overlaps both adjacent TH options: 70–80 gallons with the 300 W TH-300S and 130 gallons with the TH-800S's listed band beginning at 140, leaving a gap between 130 and 140 in Finnex's published ranges. Those table limits do not establish that a single wattage is correct for every tank of a given size. Room conditions, working water volume, insulation and the animals' actual target remain separate considerations. In particular, the 500 W model's 70-gallon floor matters; a 55-gallon setup is not within the range Finnex lists for this model.
A tube sold without its control system
The TH-500S should be assessed as an element, not as a complete integrated thermostat. Finnex's Shop product heading calls the selection “titanium tube only,” and its page states controllers are sold separately. A separate Finnex Deluxe Combo page is specifically for HC-820M plus TH tube combinations and lists a 500 W tube in that configuration. That is useful evidence that Finnex supplies a controller-and-tube arrangement, but it does not prove that the standalone TH product page includes the HC-820M or any other controller.
Finnex's combo page also says other controllers accepting three-prong heating elements may be used. That remains a compatibility requirement, not permission to connect the tube directly to a wall outlet as a thermostat-equipped heater. The HC-820M manual identifies 110–120 V, a 49.9–94°F controller setting span and a maximum 1000 W load for the HC-820M itself. It should not be read as the TH-500S's own temperature range or as a guarantee for an unrelated controller. Before comparing a listing, check whether the controller is included, whether its load and connection support the exact element, and whether the provided instructions describe their combined setup.
How the 500 W choice differs physically
At 14 inches, the TH-500S tube is four inches longer than the TH-300S and 2.5 inches shorter than the TH-800S; all three rows specify a 0.75-inch diameter. Finnex's adjacent THD-500S is a different 500 W model: the family table gives it a 0.62-inch diameter, 12.5-inch length and maximum volume of 125 gallons rather than 130. So the TH-500S is not merely another label for the THD-500S, even though both have the same wattage and a 70-gallon lower endpoint.
The TH product page describes longer internal quartz sleeves and coils than THD, and Finnex characterizes the larger surface area as supporting heat distribution and lower cycling stress. Those are the manufacturer's design explanations; this review does not treat them as measured comparative performance or proof of service life. The extra length is a practical clearance question, while the separate controller is an additional equipment and cost check. The THD's shorter dimensions do not automatically make it a better choice either, because exact instructions, the real package and the intended aquarium arrangement still need to be checked.
Material and operating claims, with open details
Finnex identifies the tube as titanium, says the metal does not shatter like glass, includes a high-temperature guard on TH models and describes the line for freshwater and marine aquariums. That supports a comparison on tube material and guard presence. It does not establish that every part of the heater assembly is unbreakable, nor does a product photograph reveal the correct setup. The reviewed manufacturer pages give no exact immersion mark, orientation, minimum clearance, dry-operation instruction or permission to install this product inline with an external filter. The HC-820M controller manual is only a controller manual, not an element-installation guide.
The electrical current basis is not fully clear across Finnex's own pages. The current family table pairs 120 V with 4.5 A in separate columns. The combo table presents 4.5 A under a heading marked at 115 V. I report the published values while retaining this reference-voltage conflict; I do not convert either figure or add an unlisted 60 Hz specification. Verify the actual nameplate and controller instructions before making an electrical decision. The Shop page displayed all three wattage variants as sold out when retrieved, but its product record is not enough to make a lifecycle claim.
Why it is kept outside active matching
The finder can compare a documented maximum but cannot test the required 70-gallon lower edge of the TH-500S range. This would create false matches below that floor if the product were activated. Separately, the listed tube-only offer does not include a documented control system, and no exact TH-500S mounting procedure was found in the reviewed sources. A helpful review can preserve the wattage-specific facts without turning an incomplete component package into a ready-to-buy recommendation, so the TH-500S remains reference-only.
The four official Shop images were visually reviewed. They depict a titanium tube with a guard and close-up construction details, but none labels the TH-500S wattage or clearly identifies its retail package. Because the current product selector covers three wattages, a shared family image cannot distinguish which tube a shopper would receive. No substitute image is used. Confirm the 70–130-gallon band, model code, 120 V label, controller inclusion and 14-inch body fit against the exact offer. Treat the capacity statement as manufacturer guidance rather than a guarantee of temperature rise in an individual aquarium.
Key specifications
Key details at a glance
| Rated heater power | 500 W |
|---|---|
| Supported water types | freshwater / saltwater |
| Electrical supply | 120 V |
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.