Auto Top Off Water Filler Aquarium Mini ATO System Fish Tortoise Tank Water Level Controller No Wiring Float Valve

Works great with a 2 liter bottle!

I have a 7 gallon tank and did not want a top off system that was too large or expensive. I purchased one of these to test it ahead of my 2 week vacation. I bought a 1 liter Evian bottle at the grocery store. It would be nice to know if other water bottles work. I have not read of other options. I can't find a 2 liter, or even a 1.5 liter Evian bottle in my area, or online, without buying a case. I am not going to do that.This design is beautifully simple and the materials are first class. It attached snugly to my tank with the included adapters. I had to dry fit it prior to peeling the tape off of the sticky portion of the adapter to make sure I had a good location. The bottle is secure, does not wobble, and will not come loose with the glugging of water being dispensed. The flow rate is low so there is not much glugging at all. I took the advice of others and cut the tubes at a 45 degree angle. You will want to do this before you attach the Evian bottle so you can get both lengths right. The shorter tube should be where you want the water to be. The longer tube can be any length longer than the shorter tube. I have mine about 1 inch longer.Hint: If you have an overflow filter system you will want to place this in the portion of the tank that the fish live. Otherwise you will have a mess if your filter clogs up and the bottle empties it's contents into the overflow.I am going through about 1 liter per week. Since I will be away for 2 weeks I am buying a second unit. When I return I will probably keep one unit attached as I am really happy with my tank always being at the right level. I think my fish enjoy that as well.

This is a great product and does exactly what it's supposed to do with minimum trouble and effort IF you use the right water bottle with it. After having it leak badly the first time I tried to install it, I discovered that most bottle of water have channels in the threads that the caps screw on to. I don't know why that is, but the bottle caps use thick plastic seals in the caps to seal them and the o-ring on this device doesn't seal well enough to keep them from leaking. After searching the comments here, I found someone who said that Evian bottles worked for them, so I bought one and lo and behold it works fine, because they've got regular threads that are complete all around and don't have those channels (see the pic for what I mean by the channels).

I sure some of these work but I’ve gone through two now and they don’t work. I don’t know if it’s lack of quality control or just plain cheap manufacturing. Some how air is getting in and the whole thing drains. I’ve used thread tape and that doesn’t work. The only thing I can think of is the cheap looking blue oring in it. To me I looks like it should be larger. I’ve spoken to the seller and they asked me to send a picture. There response was it looks correct but some how air is getting in. Fix how air is getting in is what they told me. I was really hoping it would work. This is a zero star product. I’m sure some work but I’m 0 and 2.

It's functional and can control the water level. The thing you need to notice is the tube comes with the product is not very long(around 8inch). If you use it to control the turtle tank's water level(like my case), you need to find the way to extend the tube. And need to seal the joint perfectly.

I had to take a file to it to get it to fit over my tank edge, but it’s too simple a design to fail. Would be nice if it was adjustable for width.

This product saved the tank in my office. The AC is off on the weekends and the water was evaporating too much before I could get back to refill it on Mondays, and the water parameters were swinging too much. With this guy, I set it up in a about 3 minutes and now every Friday I fill this up and pop it on top of the tank, and the water level stays constant all weekend no problem. One other nice feature of this is you can choose the size/style of the bottle you want to use, to better fit your situation. I just use a small .5 liter bottle and it works great for weekends, but if I am going away on vacation I can use a 2L bottle and things will be fine for longer. Great product!

I have two water tanks, a 55 gallon and a 29. I wasn’t able to use this w either as the rim of both tanks is too thick for the thing to even attach to my tanks. My tanks are very average and have that black lip/rim that goes all around. If your tank has one as well you won’t be able to use this product so don’t waste your money. My boyfriend thankfully has a 3D printer and is working on fudging it to fit mine.