Buying a new tank?

You really can't go wrong with tunze, JBJ or autotopoff.com. Secondary floats are always a good precaution but so is limiting the volume of your FW top off container.

Why are you keeping your top off water so far away? If that is must, your focus is the pump you'll need. Gonna need a decent pump to push 25 ft of head. If you position the top off container near your tank, all you'll need is a cheap Aqualifter which is also safer to use since it would take a while to empty your whole continer int your tank/sump using such a small pump.
 
I agree with Greech, 25' of head is going to take a strong/expensive pump, and that is not ideal for topping off freshwater. If your RO/DI filter is in the basement and you want top offs completely automated I think a better idea would be to run the output line to a container near the tank with a float switch on a container next to the tank so it is always full of RO/DI. Worst case scenario is the float switch fails and you get RO/DI water on the floor (not a common problem, but is a possibility, and a better problem than if you overfill your sump and get saltwater on the floor), and is better than causing big salinity fluctuations by using a large pump to pump water from the basement. Plus 25' worth of water coming back down a 3/4" line when the ATO turns off may cause a different set of issues. I use the JBJ w/ aqualifter on a 5G bucket next to my tank that I just manually fill up every 4-5 days (whenever I see the red light on the JBJ telling my my container is empty).
 
25' is the total line distance.. it only needs to go 6ft vertical. Its so far awat because i do not have a basement under the living room so the container would be kept under the kitchen in the basement.
 
I have a rio1700 pump that claims 7.5 head feet and it gets water to the tank but its broke so you have to hit it with a hammer to make it start.. anyone know of a good pump with about 7 head feet of capacity? should i just order another 1700 as they are cheap as heck and reliability isnt a super issue since its for an auto top off?
 
Lots of pumps will work. Mag 2 or 3 should be ok as long as there is not a lot of twists and turns. I believe the Rio will still be cheaper by a little.
 
Gotta love new toys. What size are the koralias?
 
I got a ton of frags tonight. Our local fourm did its anual bbq and raffle and i was lucky enough to get drawn quite a bit. Will post pics tomorrow
 
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