Do non-mechanical/electronic ATOs actually work?

[jason the filter freak]

Getting ready to start a micro tank, 0.5 total gallonage.

 

Im looking into a mechanical ATO like the following. Question is, are they more functional than gimmicky I don't often trust Amazon reviews. 

 

 

 

 People have already mentioned ionic diffusion isn't an issue. 

 

 I'm highly doubtful a mechanical/electronic ATO will fit and If it would hose routing would be huge vs tank size, pump output out size of a small doser would be too fast to fill and frankly I don't feel like spending $100-200 on an ATO. 

[DaJMasta]

They can work fine, the principal is straightforward enough, but if you get a tiny leak in your vessel or plumbing above the waterline, you will end up with the full ATO worth dumped into the tank in short order, so they probably work best in the format shown, where you have one complete, sealed vessel just going into the tank.

 

That said, you don't lose that much water in a small tank.  I've got a couple <5G tanks and during the summer, at least, I'm dumping in maybe a cup of top off water a day, if that.  If your water isn't too hot, evaporation isn't going to be huge, especially if it's in the vicinity of other tanks which are keeping the humidity up.  Adding a top to it may let you go days without even seeing a drop in water level, so maybe a top off every week so long as nothing in it is too parameter sensitive.

 

While it may be difficult to achieve a low enough flow rate, you could also try the old school kalkwasser doser method of just filling up a bottle with an airline and a valve, turning the valve until its a slow drip, and just letting it go.  You may actually be best served with drip rates of like 1 every 30s or a minute, but if you can get down that low you could just let it take care of regular maintenance and just top off occasionally when it seems to not drip enough.

[KingOfAll_Tyrants]

DaJMasta,

 

Intersesting proposal with the drip valve.  It seems to me that....

 

If Jason's total volume is really .5 gallons (1.9L, or 1900ml)

 

If daily evaporation for a reef tank in an average household (room temperature and normal household humidity in air conditioning) is roughly 1% a day.

 

If one drop is 0.05ml

 

Then this is theoretically easily solved.   Daily evaporation would be 19ml, or 380 drops.  That's 15.8 drops per hour, or (round down, for a 5% inaccuracy) one drop every four minutes.

 

Real world, you could try this.  That said a) I'd under drip and once the water gets to 36ppt I'd add by hand a little bit of extra rodi to get it back to 35 b) I'm told that the reliability of the drip method reduces over time due to decreased gravity/water pressure, so one might want to keep it fairly full.  ymmv.   

 

Intriguing question, though.