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What does Cobalt document for the Neo-Therm Pro 100 W tank-size ceiling?
Cobalt lists this 100 W model up to 29 US gallons. That maximum is not a performance promise; room temperature, tank cover, circulation and target all matter. The reviewed sources do not establish the exact US voltage/frequency nameplate, so this model stays reference-only rather than a finder or purchase recommendation.
Explore this need in the finder →Is the Neo-Therm Pro 100 W listed for saltwater?
Yes. Cobalt identifies the Neo-Therm Pro family for freshwater and saltwater, and lists this 100 W size up to 29 US gallons. It calls the outer casing shatterproof and the heater fully submersible. Confirm the actual unit's voltage/frequency and current instructions before use; those details remain unverified here.
Explore this need in the finder →What should I check when setting up the Neo-Therm Pro 100 W?
Cobalt says to mount the fully submerged heater with its supplied bracket and suction cups, keep it clear of gravel and decorations, leave it submerged at least 15 minutes before powering it and create a drip loop. The LED arrangement displays set and tank temperatures, while the button advances in 2°F increments; not every whole-degree value between 68°F and 94°F is selectable. Verify water with an independent thermometer and check the unit's electrical label.
Explore this need in the finder →The 100 W model is the first longer size
Cobalt lists this Neo-Therm Pro at 100 W, for aquariums up to 29 US gallons. Its overall dimensions are stated as 2.25 × 1.25 × 9.75 inches. The page does not label the axes, so the 9.75-inch figure is treated as the longest listed measure rather than an exact width/depth drawing. That makes the 100 W a different placement problem from the 25 W, 50 W and 75 W models, all of which are listed with a 6.75-inch longest dimension. Measure the actual mounting location, including room for the bracket and suction cups, before choosing it.
The 29-gallon number is a maximum, not a promise that any 29-gallon aquarium will reach a selected target. Room temperature, open-top evaporation, drafts, circulation and actual water volume affect demand. Cobalt’s current text supplies no minimum range for this model and no universal watts-per-gallon calculation. It is therefore not sound to infer that the 100 W is automatically oversized for every smaller tank or sufficient for every tank at the stated maximum. The figure is a conditional screen, not a performance guarantee.
An adjustable thermostat with a real step size
Cobalt says the electronic setting spans 68–94°F, the LED shows both the selected value and tank temperature, and the control is accurate to ±0.5°F. Those are manufacturer claims; no independent accuracy test was performed for this article. The display is useful for seeing the chosen point and the unit’s own reported reading, but it cannot demonstrate that water in every corner of the aquarium is at the same temperature. A separate aquarium thermometer is still the right cross-check.
The 100 W model advances by 2°F each time the button is pressed. That detail means a 69°F or 77°F request is inside the written endpoints but not a documented selectable point. The finder currently validates only a requested number between the lower and upper bounds. It cannot verify the two-degree increment, so this model is kept reference-only rather than returned for every in-range answer. The limitation is explicit and important: range and selectable setpoints are not the same thing.
Submersion, mounting and care
The manufacturer calls the Neo-Therm Pro fully submersible, describes its outer casing as shatterproof, and advertises automatic circuitry that shuts off to prevent overheating. For setup it directs the user to install the supplied bracket and suction cups, keep the heater from touching gravel or decorations, submerge it and wait at least 15 minutes before plugging it in. The cord should form a drip loop. Clean away mineral and algae buildup from the exterior as needed. Cobalt’s FAQ also allows vertical, horizontal or slanted positions while warning against areas of an aquarium sump with changing water levels.
These instructions do not establish a dry-running allowance or the exact trigger for the automatic shutoff. The “shatterproof” phrase does not establish that a guard is included, and the material is not specifically named in the reviewed current page text. Avoid treating a casing claim as permission to let the heater contact hardscape. During water changes and maintenance, follow the unit’s own instructions and disconnect it as directed.
Why the 29-gallon ceiling does not qualify it for the finder
The product page names the 100 W size in a U.S.-oriented shop, and the current retailer product page names the same model. However, the reviewed materials do not show the 100 W model’s voltage, frequency or amperage. A page that ships to the United States and Canada does not by itself confirm the electrical edition in a boxed heater. The exact Pro manual revision also was not retrieved. A 2012 Neo-Therm manual is a predecessor document with a different setting span and warranty, so its facts are not transferred here.
The 100 W unit also differs physically from the smaller 6.75-inch models, despite sharing their low-profile design. A 29-gallon rating may appear an attractive middle point, but exact current input and the two-degree settings remain material. The current matcher can screen the capacity maximum and broad thermostat range but cannot represent those other constraints. For that reason the public review is informative but does not create a finder or BuyerShortlists purchase link.
Use the model label as a starting check
The opened AquaCave model page identifies a Neo-Therm Pro 100 W listing, and the local listing photo shows a carton marked 100 Watt beside the heater. This exact image helps distinguish the model from the neighboring sizes; it is not evidence of dimensions beyond the listed specification, present inventory or independent temperature performance. The retailer page displayed a sold-out state when checked, but that observation is not a product lifecycle conclusion.
The 100 W Pro is worth comparing when a keeper needs a documented 29-gallon maximum, an adjustable face display and a fully submerged format. Before relying on it, confirm the actual electrical nameplate, current instructions, physical clearance and whether a two-degree setpoint lands on the intended target. The target itself should come from species-specific husbandry, not this heater’s setting range. Check aquarium water independently after the heater is installed. This assessment is based on current product information, not ownership, testing or a guarantee of fit.
Key specifications
Key details at a glance
| Rated heater power | 100 W |
|---|---|
| Manufacturer aquarium rating | 29 US gal |
| Lowest thermostat setting | 68°F |
| Highest thermostat setting | 94°F |
| Temperature control | Adjustable thermostat |
| Supported water types | freshwater / saltwater |
| Installation route | Fully submerged, in-tank |
| Heater length | 9.75 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.