boxtech Aquarium Air Pump, Oxygen Fish Air Pump with Adjustable Air Valve, Fish Tank Air Pump with Accessories Tube, Bubble Stone and Check Valve, Tank Aerator Kit

Edit (6/1):The replacement double air pump is soooo much quieter, so it really was most likely just a batch issue. I really appreciate how accommodating and willing the seller was to send me another one, free of charge, because it had passed the window for me to do an exchange through Amazon. So despite all the trials and tribulations, I'm very satisfied with both the products I now have, and the customer service of the seller.Edit (5/29):After chatting with the seller about how noisy all three of my double pumps have become, they've agreed to send me a new double pump, as it may have just been a batch issue. So I've given another star based on their customer service, and once I receive the new pump I will update again based on how well it works.Edit (5/22):Originally, I rated these air pumps highly. I had one that was a little noisy, but it was tolerable.However, over time, it got extremely noisy, and when I finally had enough, it was just past the return/exchange date. I contacted Amazon and thankfully still got a refund, and I had planned to buy another since I thought one was just a dud.However, now all three are extremely noisy. I've tried different outlets, using longer tubing or shorting tubing, switching the order of control and check valves, putting the pump on the carpet floor, on the table, on the table with a mat... nothing helps. It's extremely aggravating and it affects my sleep.The only reason it gets two stars instead of one, is that the issue is only with the double air pumps. I have one of the single air pumps and it's been silent since I got it, and is still silent.Anyway, I'm very disappointed with how all three became so noisy.Original Review:I split my two ten-gallon tanks, so I could have 2 bettas per tank, while I left my one betta in her individual 5-gallon tank. So I bought three of these air pumps—two of the double air pumps and one of the single.One of the double air pumps, and the single air pump, are practically silent. I barely notice them. However, the other double air pump is extremely noisy, and it only quiets down when I really turn up the air flow, at which point it's too strong for my bettas. I've tried using both the control valves that came with the pump, as well as other valves that came with my new filters, but nothing helps, so it's a bit frustrating. Thankfully I'm not super sensitive to the noise, so I don't think it'll keep me awake or anything, but I do wish it was quieter. It's a bit strange since the other two pumps are quiet, so I don't know if I need to change how I set it up or if it's just defective, but I'll update if I'm able to get it quieter somehow.

Very happy pushes plenty of air and is quiet. The design looks good and so far it’s functioned great! Comes with air hose, stones and check valves. I’m very pleased and will buy again.

I picked this dual pump because I wanted a lower wattage pump for a small, split tank. I love the fact that it comes with valves so you can adjust how much air is going through. In a small tank, too much air would cause too much water agitation. I've gotten it hooked up and it is working well. It's fairly quiet with a soft hum. The air stones are huge. I guess I was expecting smaller stones, as this pump is said to be good for smaller tanks. They are at least an inch in diameter and fairly fat as well. One of the stones seems damaged, and has huge bubbles coming only from the top. As I plan to replace these stones with smaller ones, I'm not concerned about it. Be prepared to have to straighten the hose. It came folded up and packed tightly into a small box, leaving many areas where the hose is crimped. That said, it seems a good product for the price.

I love this pump so much that I ended up buying 2 more. I was so amazed how quiet it is. Love the valve that comes with it to regulate the airflow. Great price all the extras.

The pump is very quiet, it doesn’t move around, and is easy to install. I can adjust the bubble flow and my fish are happy with it.

This is an excellent air pump. It's works perfectly for my 20 gallon fish tank. It's small and discreet, and super easy to put together. This air pump is super powerful but it comes with an adjustable knob, so you can make it gentle as well. And last but not least this air pump is QUIET AS HECK! Seriously you can't hear this thing at all, just a super light vibration but no sound. So all in all I'm giving it 5 stars🌟

Use this little air pump when we go get bait. Plug it into the car on the drive home and barely hear it and then it keeps the bait alive a long time! Have had bait last for over a week using it. In the long run much cheaper than getting the oxygen tabs they sell all the bait store.

This was working so great when I first got it it was pretty quiet and I loved it. After about a few days it starts making noises ok no problem unplug and plug it back and it's quiet. But a week later it's a deep constant loud buzzing noise you can hear with the door closed. Very disappointed and misleading. But other than the obnoxious noise, it works great the air stone and the tubing and all of that so it does the job just very loudly and can't get it to stop anymore.