hygger Aquarium Chillers Fan, Quiet Fish Tank Cooling Fan Equipment with Adjustable Timer Speed Controller, Suitable for Freshwater Saltwater Tanks(1-Fan Head)

my apartment gets up to ~80-85 in the evenings during the summer. I have a 10g tank that was also getting up to ~85, and attaching 2 fans on the lowest setting dropped it from 82 to 78 in 2 hours (stopped watching the temperature after that), while my apartment ambient temperature was roughly 83. all the settings are quite quiet, though i haven't had the product for long and it seems like similar items to this may develop louder noises due to their own vibration & build quality. none of that so far though. very happy with efficacy and ease of use for this item. for a rough idea of the sound level, on max setting, you'd hear it if it were in your room at night, but it's not particularly noticeable during the day with any other sounds going on. for the lowest setting, you have to get very close to hear it running.another reviewer reported that you could set this up with a temperature controller. I'm thinking of doing that, looks like to do so, you just skip the speed&timer controller piece in the middle of this setup. the wall adapter can plug straight into the 3-way power splitter just as easily

I’m amazed at how good these gas work. I have a 125 freshwater tank and last week the temps started to hang out higher than I would prefer. Got the fans, only used 2 of them and they run all night on my acrylic tank. They have successfully got temps down from 84 to 79.

It does a really good job cooling off my aquarium and is quiet on medium or lower. It will actually drop the temp by 2°F in less than an hour. I put it on a timer so that it only came on periodically a few times a day but you can’t use the timer with the little controller that comes with the fan. Whenever the timer tries to kick it back on, the controller stays off and has to manually be turned on. Hyger gave you a way to bypass the controller but then it defaults to full blast and it’s a little noisy on high. I’m gonna keep it and make it work because it’s the best option I found so far to cool my tank off.

I like the timer and ability to split and move the individual fans.

A feature I don't see mentioned in many reviews (or even in the included manual) is that the included controller can be bypassed if you are using a thermostat like an inkbird with heat/cool capabilities and you want to leave the fans in an always on state so the thermostat can do its thing. I saw negative reviews complaining about this, so wanted to leave a review as I was purchasing another second set. Yes, those reviews are correct in that when power is cut then comes on again, the controller will not turn the fans on until you press a button on it.But, you can just ignore the included controller. Just put it to one side and connect the fans directly to the power supply (its the same plug), then switch the fans to 'on' at each unit. This creates an 'always on' state that can then be controlled by any other controller you want to use (that work by controlling power to an outlet).

Speed:It has 5 speed levels but to be honest, it doesn’t create enough air movement for me. Even at top speed it feels like a soft blow. Even with all 3 fans going it barely dropped my temp.Value for money:Great value for the moneyNoise level:Very quiet

This small fan literally cools off 10 gallons by a few F in half an hour

I was skeptical after Amazon posted this is a frequently returned item. I wanted a simple to use, effective cooling fan to use with my inkbird controller. You just plug the fan directly into the controller and skip the fan controller they include . The bottom line is this will cool your tank. Best of all, it can be used on a Fluval Spec 5 tank .