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

I bought this to use as an ATO for a Fluval EVO 13.5 saltwater setup. I didn't want to spend a ton of money on an electronic ATO for this little tank and didn't have the space in my office for one. This was cheap and simple so figured was worth a shot. I've had it on the tank topping off the 3rd chamber (return chamber) of the tank for 2 weeks. It has kept the water level constant and I have not seen any variation in salinity (checking using refractometer). The constant water level has also made the PS2 protein skimmer run more consistently without having to fiddle with the micro adjustments any more as well.

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 couldn't be happier with this product! I bought this to maintain my water level while I was away on vacation for a week. In the winter my small (5 gal) aquarium evaporates off water very quickly, and if the water level falls too much my heater and pump turn off - which is no good for a tropical aquarium. After finally locating the Evian water bottles it requires, (I had to buy a case, which cost almost as much as this product) I assembled the filler, (which was very simple) stuck it on my aquarium, crossed my fingers, and left for vacation! I half worried all the water would drain out, overflow my tank and ruin everything while I was away, but when I returned, the water level was right where it needed to be and there was no indication of any spillage. It had used the entire bottle in that time. The only limitation to this product in my opinion is the capacity, since you are limited to the size of the bottles you can locate, but for me, 1 liter was enough for 1 weeks time. I would highly recommend this product for an effective, inexpensive top-off device.

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.

This is not the easiest to setup but for the cost it’s worth it. I first tried with a 2L Essential bottle because that was the biggest bottle I could find at my grocery store. It did not work with the adapter, nor did it work when I tried to use electric tape to have a tight fit. There was still a leak. I switched to a 1L Smart Water bottle and it works like a charm, with the adapter.

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.

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 thing works awesome with an Evian water bottle. So many people on here writing a bad review because they can’t follow directions and use the bottle it is made for. Other people writing bad reviews cause they can’t afford a rimless tank. This clearly shows it’s not for rimmed tanks. One guy said that it’s not meant for people with fancy rimless tanks because they can afford fancy ATO systems. Not a single picture shows it on a rimmed tank. This thing is great, it’s a great value for a simple easy ATO