Running Top-Off to Sump or ATO?

[Megability]

For those that have piped in plumbing from an external water station, do you have top-off going directly to your sump when needed, or do you fill your ATO reservoir when needed, then let that top-off the sump?
What’s best and why?
Thanks!

 

[rhostam]

For those that have piped in plumbing from an external water station, do you have top-off going directly to your sump when needed, or do you fill your ATO reservoir when needed, then let that top-off the sump?
What’s best and why?
Thanks!

In my existing AIO and in my new peninsula build, I have RODI water going directly into an ATO reservoir (water level maintained by programmable valve and protected by sensors and a mechanical float valve) and use reservoirs to top off sumps (via an ATO kit).

I think it is safer than having RODI going directly into your tank.

 

[New&no clue]

I have mine go directly from my mixing station to my sump.

Pro- You don't have to buy and ATO container. You don't have to remember to fill the ATO container.
Cons- could quickly overfill your tank with fresh water, leading to flooding and severe decline in salinity.

To mitigate that risk, I use the tunze ATO, which has multiple sensors and fail-safes. However, it is still a risk.

 

[Gtinnel]

I have my mixing station refill my ATO reservoir whenever it needs to. However, I only have mine setup that way because it was the easiest way for me to do it at the time. I don't actually pump the water to my ATO I keep a tube at full siphon from my ATO to a bucket (at the same height) in my mixing station. In the future I plan on using my mixing station to pump the water directly to my sump to free up some space under my stand.

 

[Bad Company]

I have a reservoir fed by RO with a mechanical float switch. If the float switch fails, then the overflow goes down a hose into the drain, and the RO filter shuts off after 30 minutes anyway.

In the RO water reservoir I have a pump triggered by two float switches ("top-it-off") system that refills the sump as directed by the two redundant float switches.

The RO reservoir holds about 28 gallons enough for about 3 weeks of top-off water. I love this system, as I never have to worry about re-filling the reservoir.