Cobalt Neo-Therm heaters are very unique. They have a super thin profile that allows them to fit into tight spaces like on AIO compartments, or sump baffles. With its easy to set and easy to read control system, setting a heater has never been this easy.
- Easy to set "One Touch" control
- Advanced electronic thermostat - Accurate to ±0.5ºF
- LED Display - shows the Set Temp and Tank Temp simultaneously
- Set temperature range from 66ºF up to 96ºF
- Safety features
Safety Features - integrated thermal protection circuitry shuts the heater down before it can overheat. The outer casing is shatterproof making the NEO-therms virtually indestructible. Use for freshwater and saltwater aquariums and terrariums.
Correct heater position- Vertical with heating element down, bezel, cord, and button up.
- Minimum water level - Top of the bezel.
- For 25, 50, 75 Watt - 5.5" from bottom of the heater
- For 100 Watt - 8.75" from bottom of the heater
- Maximum depth of 31.5" deep at the bezel
Quick Compare - Cobalt Neo-Therm Submersible Aquarium Heaters
|Model No.||Maximum Aquarium Size||Dimensions|
|25W||6 Gallons||6 1/2" L x 2 1/8" W x 4/5" Thick at Bezel|
|50W||12 Gallons||6 1/2" L x 2 1/8" W x 4/5" Thick at Bezel|
|75W||20 Gallons||6 1/2" L x 2 1/8" W x 4/5" Thick at Bezel|
|100W||29 Gallons||9 3/4" x 2 1/8" x 4/5" Thick at Bezel|
|150W||40 Gallons||10 7/8" x 2 1/8" x 4/5" Thick at Bezel|
|300W||75 Gallons||10 7/8" x 2 1/8" x 4/5" Thick at Bezel|
Note: 300W model consists of two connected heating elements that measure 10 7/8" x 2 1/8" x 4/5" each.
Great Accurate Heater By Hannah on 7/12/2018Hannah would recommend this product to a friendI've been using this heater on my nano reef for almost 6 months. I find it to be very accurate and keeps the temp very steady. The only negative I can find is the price but I guess you get what you pay for.
Overheated my tank. Killed everything. By NewReefer91 on 5/24/2018NewReefer91 wouldn't recommend this product to a friendCaution. may get stuck on and cook nano tanks. ruined the hobby for me.
150 watt cracked By 120reefkeeper on 4/26/2018120reefkeeper wouldn't recommend this product to a friend150 watt date code on the cord by the plug of 8/2017.
Split down the side and tripped the breaker. No real damage to the tank as of yet. Only in service 3 months.
Heater Burnt Out In 1 Month By Jody on 4/26/2018Jody wouldn't recommend this product to a friendI purchased this heater for a 120 Gallon. This heater is working great in my Nuvo 40 and I watch BRS videos all the time. I knew this was the heater that was going to be recommended and on my new aquarium I wanted nothing but the most reliable. After 6 weeks there was an electrical smell coming from under the aquarium. After seeing the heater it was leaking gas out the side. It smells like chemicals. When pulling it out I felt dizzy from the chemical smell coming from it. I reported this to cobalt and reported that I had lost an expensive fish. They reassured me that the product was safe. I don’t agree that breathing in gas that smells like chemicals and losing a fish to this is safe. The scientist at cobalt said they add chemicals so you can smell a failure and that it is perfectly safe to breath in. Cobalt is willing to replace the unit but the fish I lost cost more and was more important to me. I wouldn’t recommend this product to anyone.
Heater exploded, smelly greasy goo By Polarcollision on 3/22/2018Polarcollision wouldn't recommend this product to a friendHeater exploded—literally—this morning. It spewed nasty smoke and an orange greasy goo everywhere. After a quick google, this is too common of a problem with this line of heaters.
Works great By Bhack on 1/9/2018Bhack would recommend this product to a friendI only have had this heater for a short period of time but have fallen in love with it. It is a great heater. It’s slim design and accuracy make it perfect for my Nuvo 20. I have seen many negative reviews about this heater but, if you look at all the other heater brands, they have negative reviews too. Most of the issues could have been prevented by use of a temperature controller. If you spend a few hundred dollars on coral but then go cheap on your equipment, you are asking for a crash. Example: I had a battery operated auto feeder come loose from a mount and fall into the tank right after I left for work. My Apex sent an alarm text to my phone saying my ORP was below 200. I wasn’t able to get home until 9 hours later but, I was able to pull it out of the tank in time to loose only one coral. I have an sps dominant tank with very finicky acros. Moral of the story, don’t buy cheap autofeeders that mount on the tank and have some redundancy. It at least could save your tank from overheating or tell you that you have a problem.
Cooking Corals By Brain on 1/7/2018Brain wouldn't recommend this product to a friendI have the 150w version. This heater worked fantastic until a momentary power outage. Then the heater shot straight to 94 degrees and turned my coral tank into a jacuzzi. Control no longer functions and it is stuck on 94, Not impressed.
Neo-Therm Submersible Heater - Cobalt Aquatics By Bearclawws on 11/23/2017Bearclawws would recommend this product to a friendI wouldn't use anything but these. I have 8 of them and honestly they all have been running over 3 years now in multiple aquariums with no issues with any of them. I'm picky and I rarely 5 star something, but this deserves it. I can't think of anything to change about the design and they look sleek and cool.
1. I like to place them where I can see the light. But thin enough to go hide out of the way.
2. I will not use glass heaters in my aquariums, been there, done that, learned the lesson the hard way.
3. Sometimes I needed to pull one out of the water a second to move it into a different chamber, not recommended while plugged in, but I found it won't hurt them, just don't leave them out of the water but a few seconds. I accidently left one out for over 20 minutes by accident once, it was hot but no issues.
4. I've dropped them multiple times, stepped on one, and it's no big deal, but if it was glass it would have been.
5. I have a heater in my 65 gallon saltwater vertical mixing containers and I use these because they're not going to get damaged in there with the pump mixing the water like a washing machine, glass heaters would bang around and hit the pump.
Too much $$ for a premature failure By Reefer Reborn on 11/2/2017Reefer Reborn wouldn't recommend this product to a friendYou will be extremely impressed with the product keeping the temperature within a half degree day in and day out until suddenly it stops working after 2 months. My unit was blinking current temp slow Yellow LED and Target Temp solid Green LED but was not connected to the heating element. It could have been worse and got stuck on in the heating mode (Negative Star review for sure) but thank God Cobalt has a system to prevent that. The friendly staff a Cobalt are sending a new one and I guess I will try it once more because I love the =/-.5 degree so much. If doing it all over I would just by a classic heater and or one of the fancier ones and an external controller. perhaps when I get my corals in I will buy a 77.5 degree Walmart one to back this one up so the drop is not 5 degrees over night from 78/79 my target temp.
I've loved these heaters so far, but I'm going to remove them anyway By Randall on 10/2/2017Randall would recommend this product to a friendLooking at the other reviews, it seems that a fair number of people have significant issues with this heater. That is unfortunate because the design is fantastic; this thing is almost impossible to physically damage accidentally. And the temperature regulation by the internal thermostat is top-notch, possibly the tightest control available in a heater-thermostat combo.
I am running two 200W NeoTherms in tandem, with the internal thermostats set to 80 degrees F, but actually controlled below that level by an Apex and it's temp probe. In order for overheating to occur, both one of the heaters and the Apex would have to fail at the same time; not likely. For underheating to occur, both heaters would have to fail. Again, not likely. With this setup, I can easily maintain my tank temp within 0.5 degrees F, day and night.
It doesn't take much searching to discover that these heaters have caused some people utter disasters. Starting around 2014, people would find that the 200W version, in particular, would crack open, spewing out crud into your water, and smoke and vaporized epoxy into the air, killing virtually everything in the tank and almost impossible to completely clean out afterwards. Complete disaster.
This problem was mostly seen with the 200W version (which you'll notice BRS no longer carries, although it's still produced). Cobalt claimed to have re-designed the heater by 2015 and the online complaints largely subsided. Problem fixed? Well maybe not. I just saw a recent post about a 150W version with confirmed production date 8/16 that did this - huge crack down the length of the heater, crud all over it, sump trashed, dead tank, house smelling like burnt plastic.
So, NOPE, can't have it, even if the risk of it happening is a small one, it's too much considering the magnitude of the disaster if the case on one of these heaters cracks. Glad I came here to do this review, otherwise I might not have known until it was too late. Going to buy a couple of Eheim Jaggers now.
Works great for me By Kenae on 8/23/2017Kenae would recommend this product to a friendNo real issues, read a few complaints on this heat but I have yet to have any of these issues. All in all it works great. Goes about 1/2 a degree higher than I set but it's good.
Shocked By Kecked on 6/30/2017Kecked wouldn't recommend this product to a friend150w heater failed and shocked me. No idea why. Killed some coral too
I have a 2 1/2 gallon tank for my betta.
Is the 25Watt Neo-Therm ok for me to use in my tank?
I would like to set it about 78 and hold it there.
My last heater rose the water to almost 88. Not good.
Typically 2.5-5 watts per gallon are recommended. While the 25 watt could work if left on the lowest setting and certainly can work well with safety built in it has the potential to over heat if left on too warm of a setting.
I have a 94 gallons tank.
What kind of cobalt heater do I need, how many watts
You will want 2 of the 200 watt heaters for good coverage of your tank! Feel free to let us know if you have any further questions!
I have a 46 gallon bowfront with a 20 gallon sump, given water displacement from live rock and filter media such as protein skimmer and reactors and live sand, would a 150watt be sufficient enough to heat the tank?
Have a great day!
How many amps does the 200 watt heater pull?
We expect around 1.6 amps. Feel free to let us know if you have any further questions!
Can these be mounted horizontally? The manual from cobalt has a big X in a photo over them being sideways, and only shows them OK upright. Your overview here says they can be submerged at any angle though... don't know how anyone would fit anything 100w and up completely underwater in a sump straight up and down.
Regrettably, the quick overview is incorrect. This heater should not be mounted in any position other than vertically, with the cord and buttons at the top. We will get that updated ASAP. Have a great day.
Just bought a Nuvo 20 from you guys. The chart says 75W for 20 gallons, so should I just follow that or would 100W be more reliable?
Heaters are one item that I would not recommend going higher than what you need. If the thermostat were to fail in the on state and you had a larger one in the tank it would cause problems faster. I would stick with the 75 watt recommendation.
If you have any other questions please let us know!
Will this heater shut off if it is not all of the way in the water? When doing water changes on my solana, the area that the heater will go in will be out of the water for a few minuets
It won't shut itself off (I don't know of any heater that would). You will want to unplug it before its removed from water (or if you have an aquarium controller you setup something like a feed mode to shut down your pumps, heaters, etc at the press of a button for when you do a water change).
Is there a calculator that helps you determine what sized heater I need for each of my tanks?
There isn't a calculator as each heater is a bit different, but all of the manufacturers do have recomended size aquariums for their heaters. If you look at the full details of this page there is a quick comparison chart to help you match the heater size to how big your aquarium is.
I have a 10 gallon tank right now. I also have plans in the future to expand my tank size to around 20-30 gallons in the future. If I buy the 100 watt heater now and put it in my ten gallon tank with the idea of using this same heater in the future would it be complete overkill? Would putting in this high watt output heater be detrimental on the 10 gallon tank?
Thats not a problem at all. If the heater is larger it just won't run for as long, nothing to worry about!
I am in the process of setting up a 40 gallon hex reef tank, and would like to get a recommendation for a heater. I am not wanting to get the latest and greatest model. Just something reliable and not glass.
Most of us around here use the Neo-therm but the second most popular has to be the finnex HMO series heaters. Assuming you don't have an aquarium controller yet I would get something that has a digital thermostat as they are a lot less likely to fail (in particular in the ON position).
I'm just waiting on the Apex gold to come out. I want to put an 85 gal coral frag/semi show tank together. With the Apex , can I run two cobalts in tandem or do i need a bigger heater than the biggest Cobalt Neo therm? I think its only good to 55 gallons . Plus I have the sump volume aswell do factor in.
I think they should be here this week :-) The different outlets have different amperage allotments but in general unless you are using two very large heaters your not going to run into any issues :-) Just for example, the 8amp outlet would be able to power about a total of 950watts. Should be way more then plenty for a 55g tank!
Once the temperature is set, if my Apex unit cuts power to the outlet (temp gets out of range) does the heater remember the last set temp or does it reset to a default? If it is a default, what is it?
The heater should remember the tem, but that said with a setup like this what you would want to do is set your heater for your desired temp (say 78 degrees) and then set your Apex as an emergency cutoff to cut the power if the temp gets too hot and it appears the heater has failed (say 79.5 degrees). That way the heater is in primary control and you will avoid constantly cutting power to and from it (which may be hard on the heater).