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What is the QPH-400's source-supported upper tank band?
AquaTop's manual and cutsheet give QPH-400 a band of 80–130 US gallons; its exact retailer product image also shows a 130-gallon carton maximum. The model is 400 W, 17 inches long and identified by UPC 810281019567. The upper edges agree, but that does not promise a specific room-to-water temperature rise or prove that the lower 80-gallon edge is a safe minimum for every setup.
Explore this need in the finder →Is QPH-400 documented for marine water and adjustable control?
Yes. The QPH family manual describes fresh- and saltwater aquarium use and a top-mounted adjustable thermostat; the cutsheet lists 68–93°F. It can be mounted vertically or horizontally inside the aquarium, with suction cups. These facts do not establish a digital display, accuracy tolerance or shatterproof body. Confirm the exact package and use a separate thermometer.
Explore this need in the finder →Why does QPH-400 stay outside active finder recommendations?
The 80–130-gallon band has a positive lower edge, and this site's numeric rule can only screen the upper edge. Treating the model as active would also return it for below-band volumes. It therefore remains a reviewed reference instead of a candidate, even though the 130-gallon maximum and exact configuration are documented. Check the 17-inch body clearance, waterline, room temperature, circulation and exact package rather than relying on wattage alone.
Explore this need in the finder →The AquaTop QPH-400 is the largest size in the observed Quartz Platinum family: 400 W, 17 inches long and listed for 80–130 US gallons. The official family table and the exact image’s “130 gal. max” carton agree on the upper number. That agreement is useful for identification, but a maximum rating is not a promise that the heater can meet a particular target temperature in every room. This is an evidence-based review, not a hands-on test.
Large capacity and the lower-band question
The QPH manual and cutsheet identify five separate wattage configurations. For QPH-400 they give an 80–130 gallon band; the exact retailer image also shows a QPH-400 / 400 W heater body and a package maximum of 130 gallons. The manufacturer’s lower value is a stated band edge, not proof of a universal safe minimum. Room temperature, tank cover, water flow and actual working volume can change what a system needs. The manual specifically notes that a room 10°F or more cooler than the selected target may require more wattage.
Because the manual gives a positive lower edge, this site does not list QPH-400 as an active volume-finder candidate. The current matcher only checks whether a model’s maximum is at least the entered volume; it cannot exclude an aquarium below 80 gallons. Returning the QPH-400 for a much smaller tank would therefore exceed the documented band. It remains available as a fully reviewed reference, not a buying recommendation.
Adjustable analog control and independent verification
AquaTop describes an adjustable top-mounted thermostat and lists 68–93°F for the family. The manual says the indicator light turns on during heating and goes out at the target. It does not state a numeric accuracy tolerance, and the light is not described as a digital reading of the water. Use species-specific care information to select a target, then check aquarium water with a separate thermometer in a representative location away from the heater.
The automatic target shutoff described by the cutsheet is a control behavior, not an independent overheat guarantee or a measurement. Do not infer performance from “heats quickly and accurately” marketing copy; those words are AquaTop’s claim, not a measured result in this review.
Confirm the 17-inch placement envelope
The product image and manufacturer family data identify the QPH-400 at 17 inches. The QPH manual supports full submersion inside the aquarium, vertical or horizontal positioning and suction-cup mounting. It requires the water to remain above the marked minimum line and recommends good flow around the heater. Measure the installation space and account for the top dial, cord routing, waterline, access for cleaning and removal, and the complete body length. The source does not document inline use with an external filter.
Follow the manual’s stated acclimation and cool-down waits: allow 10–15 minutes before installing or removing; after installation, wait at least 15 minutes before applying power; after unplugging, allow at least 15 minutes before removal. Arrange a drip loop and disconnect power before maintenance. Do not use a cracked or damaged glass heater.
Marine use, quartz construction and label checks
The manufacturer manual explicitly includes fresh and salt water and calls the body shatter-resistant quartz glass. That phrase is not equivalent to “shatterproof”; no impact rating or included protective cage is established. The exact image’s body label reads QPH-400, 400 W, AC 110–120 V / 50–60 Hz. This is a visible label observation tied to the exact listing image, not a performance or certification test. Confirm the physical model and electrical label on the actual unit before use.
How it differs from the smaller QPH models
QPH-50 is 50 W and 9 inches; QPH-100 is 100 W and 10 inches; QPH-200 is 200 W and 13 inches; QPH-300 is 300 W and 15 inches. The QPH-400 extends the length to 17 inches and the official tank band to 80–130 gallons. The smaller models have their own capacity-package conflicts: the QPH-100 image says 25 gallons maximum against a 20–30 gallon official band; QPH-200’s image says 55 against 40–60; QPH-300’s says 80 against 55–100. Do not transfer those claims to QPH-400, whose upper number agrees.
The 2021 manual and 2022 cutsheet do not establish current lifecycle or stock for every QPH size, and the exact QPH-400 page did not reopen this cycle. That is not evidence of discontinuation. Check current written product and warranty information, exact SKU/UPC, physical electrical label and your aquarium’s conditions before purchase.
Sources: AquaTop’s QPH owner manual and Platinum heater cutsheet provide family specifications and instructions. The exact-model image is from the QPH-400 listing and is used for identification only.
Key specifications
Key details at a glance
| Rated heater power | 400 W |
|---|---|
| Lowest thermostat setting | 68°F |
| Highest thermostat setting | 93°F |
| Temperature control | Adjustable thermostat |
| Supported water types | freshwater / saltwater |
| Installation route | Fully submerged, in-tank |
| Heater length | 1.25 in |
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.