Pump on timer for simple auto-topoff

[trilinearmipmap]

I have a sumpless 30 gallon cube with a mostly closed top.

I want to set up a simple auto-topoff. I figure the tank will evaporate a few hundred mL per day. I'd like the auto-topoff because a fluctuating water level will affect the performance of the in-tank skimmer (Tunze 9002).

I figured a small pump attached to an electronic timer going on for maybe a minute or two per day. Maybe a maxijet or an aqualifter. The pump needs to raise the water about 4-1/2 feet. Maybe restrict the flow on the output so the flow rate is slowed down making it easier to adjust the amount of output with a timer. Then once a week or so I can adjust the water level manually.

I don't want to invest in an osmolator (have one on my reef tank). And a dosing pump is expensive for this application.

Has anybody done this and what kind of pump did they use?

[Chin_Lee]

i would prefer two float switch each encased inside a small 35mm film holder to prevent snails or critters from interferring with the float sensor. One set to turn on and other set to turn off at certain levels. the price would almost be the same as that of a timer and more reliable.
personnally I use the jbj autotop off and its worked well for me.

[Clown]

Used a float switch From a humidifier ( Can be bought from home-depot )
And i connected that to a purified water filter



Sorry there so large.

[Clown]

Mabey Not quite what your looking for but i only cost about 15$$ for every thing.

[Clown]

(and you could mount that in your top tank)