I would think a 50w would be fine, assuming you get a high quality heater that turns off when it reaches its desired temp. Otherwise, there are 25w heaters out there. In either case, the Cobalt Neo-Therm line of heaters is recommended a lot (pricier compared to glass heaters, but no worry of breaking).

No matter what option you go with, a temperature controller is also something to look into. Can't speak for any particular brand myself though.

 

Decided to research this heater it's $109.60!!! with tax here in Canada for 150w. I just got an eheim Jager 2 weeks ago from petsmart during their 25% off sale for under 30 taxed and it's the most accurate heater I own.

 

With that small tank and 50 watt, I would not touch it! A ten gallon can go from okay to cooked and dead in less than 6 hours, so I might guess the time on 2.5 as maybe around 2-3 hours?
So when I was faced with wanting no heater showing as well as a much smaller heater, I went DIY. This is a link to what I did at the time but it is not much help now as all the pictures are lost due to various computer and photo sharing changes.
http://www.plantedtank.net/forums/20-diy/927097-no-equipment-seen-challenge-3.html
Basic idea of the project is that I built a box for the tank to set on and hide lights at the base, rather than have a heater in the tank. Small needs little heat so just a set of light bulbs or other simple heat might fit for your use? Tied to one of the simple $10-12 temperature controllers, the set can be very cheap --if the DIY is of interest.
One of the turtle heating pads, tied to a controller might be an option, as well.

 

I use Hydor 25W Submersible Aquarium Heater for my 3 g, also placed it in my 2.5 g for a week. It's adjustable so you don't have to worry about turning it off like other cheaper heaters. You just have to adjust the heater to lower value you want it at because it's a smaller tank. Like if you want it at 80 degrees then place it at like 75 degrees or something around that.

https://www.amazon.ca/gp/product/B0006JLPG8/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

 

Question is being in Florida do you even need a heater for shrimps?

I am at NJ and none of my shrimp tanks have heater including a 2.5gallon and 1gallon. Room temperature stays above 63F.

 

well the water ends up staying around 70, but is that acceptable for the shrimp? seems a little chilly and on those little aquarium thermometers its just below that little green area.

 

I have a small 2.5 gallon betta tank that he is chilling in while his 20 gallon gets totally set up. I have this submersible heater that raises the temperature about 4-5 degrees above room temperature and works pretty well. It actually shuts itself off and has not cooked my betta.

I'm not sure what stores in your area would have it, but I found it on amazon for you. I bought it at my local pet store. Hope this helps

 

Funny this is asked. I have the heater referenced by @sorepatrol68 and walked in to work this morning to find my Betta had past on.

Long story short, I grabbed a thermometer from home and at 2 pm the water was 92 degrees and the heater had not turned off all day.

I'm not necessarily knocking the heater itself because I know this can happen with any piece of equipment, but that 25 watt heater raised the temperature from the 78 it was set at well over ten degrees over the weekend.

I would either make sure you need it or consider investing in something like a controller.

I'm also in Florida and the office temp in the office is averaging 76. In retrospect, I should have left well enough alone and not added another possible failure point.

Sent from my XT1095 using Tapatalk

 

Omg.... I'm sorry for your loss

So far my sister and I haven't had any problems with this heater. She has it in a 5g and I have it in a 3g. We also live in Vancouver, Canada where room temp is about 20 degrees Celsius and my room is about 25 when I turn on my heat. Maybe your existing room temp is enough? Or the heater is faulty...

How big is your tank btw? @psych

Sent from my SM-G930W8 using Tapatalk

 

I'm guilty of not having a thermometer in the tank, but I will from now on. Unfortunately it probably wouldn't have saved Fred since this happened over the weekend.

I know he has been alright in the past without a heater so I think I'll probably go that route. Even if he's a little cold at least he won't boil. Poor guy.

Sent from my XT1095 using Tapatalk

 

The point that newer folks may miss is that the heaters are one of the most dangerous items in our tanks. We do all kinds of things to avoid chlorine, ammonia, nitrates and ignore the simple heater as it just sets there in the corner. That is like walking past a ticking time bomb!
Electro-mechanical things fail, right? Some last longer than others but heaters are not one that are known in our hobby as a good piece of equipment .
So the question is not so much if they will fail but how to keep it from doing us in if/when it happens.
I won't even say it happens often as I have only had it happen three times in nearly fifty years.
But the really big thing that sticks in my mind is that it can totally wipe out the entire tank and that is just really a downer that I do not want to happen again.
Total up what you have spent on the tank (time, effort, and money) and then ask how you will feel if it is all dead tomorrow.

 

I've purchased and returned those 25W (fixed and adjustable) heaters sold in the pet stores. They just felt cheap, even though they technically worked. All heaters can fail, but I feel more comfortable with Aqueon Pro and Eheim Jager.

I'm using an Aqueon Pro 50W in a 2.5 gallon right now for newborn fry, and also in a 10G. I use the 150W in a 40g. The glass is coated in heavy black plastic so it won't break, and it blends into the tank better than the others. I have Eheim Jager for larger tanks, but never tried them smaller because they run slightly longer in length. Their calibration is nice.
The best price seems to be Amazon, often 1/2 of the stores.

I keep my Bettas at 76F although they can handle low 80's. I kept one unheated in the winter and the tank (bowl) was as cold as ice water when returning from a trip - heat was off in the house. That was before I knew tanks were heated (he was a gift and my only fish). I share this because other tropical fish wouldn't survive these temps, and Bettsa are quite hardy.

 

Thanks for saying this.. if I try again I'm going to skip the heater at first and hope the office stays warm enough. If I do need one though, you can bet I'll monitor it daily.

As an aside, and apologies for derailing if I am, can someone help me understand why controllers are so often recommended? I assume that the controller also has a thermometer that would allow it to past voltage to the heater. If the heater goes bad and stays "stuck on" and the controller then goes bad, wouldn't one end up with the same mess? Or do controllers go bad less often?

 

75 - 76 F is perfect. I wish I could hold that temperature. I'm in Florida but am in an older house which is a 2 story and the thermostat is on the 2nd floor. In the winter, if I have it set at 68, it may get down to 59 - 64 in the winter on the first floor. We get 8-10 freezes a year. Some down to the teens.

 

Amazon sells a selection of "under tank heaters" with a similar function to the DIY box described by PlantedRich.
Basically a small heating pad, which might be a useful tool to help you through those colder nights.

 

hmmm well ended up getting that adjustable Hydor 25 watt. Probably just going to keep it set below what i actually want it to be

 

For what it's worth I still like that heater even though it boiled my Betta. It was one of few with that low wattage that was also adjustable at the time I was looking. Most were preset. It also got fairly positive reviews if I recall.

I would just encourage you to keep an eye on the temperature with a reliable thermometer. Maybe something digital so it's easy to read and you can just see it in passing.

Good luck!

Sent from my XT1095 using Tapatalk