Basic and bullet proof DIY ATO?

[Squatch XXL]

I've always been a homebody, so ATO systems are just about totally useless. However I am planning a long weekend in the next month, and would like some sort of suggestions for an ATO.

I have done some research and would rather have first hand reports. I need totally mechanical, and turn my nose up at anything that uses electric. I am looking for something "modular" that I can get out when needed, and hide when I am back at home (99.99985% of the time).

The less chance of individual component failure, the better. Aside from that I don't plan on using more water in the container than can really screw up my system during a total failure.

I was honestly going to diy rig up a toilette float valve, but as a plumber I know how often they fail....let alone to have it sitting in salt water.....I don't think it would last more than a few months. I am not beyond drilling out a sump, but would prefer not to.

 

[DaveK]

In my opinion a mechanical only ATO can not ever come close to working for any length of time with out a failure. Period. This is because no mater what you do you have a single point of failure. You just can't get around it without electronics.

If you do insist on a mechanical only system, to keep things from getting totally out of hand, you need to limit your top off water to only a few gallons, but this has it's own problems. A reef can easily evaporate a few gallons a day. My own system can evaporate a bucket of water a day in the winter, or when the air is on a lot in the summer. Dry air in both cases.

Here is a typical float valve you could try. It would need to be mounted to the sump by drilling (offsite) - http://www.bulkreefsupply.com/reverse-osmosis-float-valve.html Note that I do not recommend this method.

I know you said you doing want an electrical based ATO, but something like this is what I'd recommend (offsite) - http://autotopoff.com/products/DS1/ Note the use of double float switches . Now if one fails in the closed position, the second one will still shut off the pump after is adds a but more water to the system. This system also uses a relay to prevent anything but low voltage power fromm going thropugh the switches. You would also need a small pump to make this work,

 

[rostervandross]

What kind of pump does one use to put into your ATO reservoir?

I am beginning to research and plan an ATO to hook up to my sump. .. I want it to pump into my return chamber and have the sensor there as well, am I right?

 

[DaveK]

Many people use those small, inexpensive aqua lifter pumps. They work but they are somewhat prone to fail. It's best to have a backup pump available with these.

Other people use a small powerhead. This can work too, but delivers a lot more flow, possible more than you want.

Adding makeup water is usually best done at a high point in the system, usually the overflow in the main tank. This prevents the top off water from siphoning into the system, even with the pump off. It also allows for better mixing with the existing SW.