Is an ATO 100% necessary?

[PolypPocket]

Do you really absolutely have to have one? Or can you get by with topping off a few times a week?

I’m new to reefing and just set up my two mini tanks. The biggest one is 6 gallons and has a lid that covers about 80% or so of the surface so I obviously am going to get some evaporation. But I’m wondering how much of a “must have” an ATO is? I never used one in the olden days (I’m back after 15+ years away from saltwater, never had corals though).

The tank won’t have any priceless corals but I still want to do what’s best for whatever ends up going in there (still cycling).

Anyway what do you think? Can you get by without one just doing top offs, say, 1-2 times a week? What if an ATO malfunctions (I’m actually scared of that happening)? Can you get away with something like this or does it need to be top of the line?

https://a.co/d/04dGjoB2
Thank you in advance

 

[TylerHaworth]

I can't imagine life without one.

SPS = Stability Promotes Success

 

[mfinn]

It is just one of many tools we can use to maintain saltwater tanks.
Short answer, no, you don't need one.
But they are very handy. Life gets busy and we forgot minor chores.
On small tanks it is easier to get by without one.

 

[PPBlimpy]

No it is not. But I swear when I added mine it is what was the final piece to stability.

 

[Michael Hughes]

No it is not 100% necessary, but it is 100% worth it.

 

[gkprevite]

An ato is important for stability especially in a small tank. I’m running a similar one as your link for 2 years it’s been pretty solid

 

[sjfishguy]

Not necessary especially for a 6g tank with a lid as you describe. Just keep a gallon of RO water nearby and poor some in now and then. To be honest an ATO on that tank would be more of hassle than it’s worth. This is what I did back 25 years ago when I had my first nano. Have a 180 now and an ATO is a must

 

[Airedale Reef]

No it is not 100% necessary, but it is 100% worth it.

This

 

[Hunna’s Stunnas]

ATO is the only piece of equipment you need outside of your filtration/water movement, lights, and heater. All 4 of my tanks all run with just that and I have 3 high-end SPS in a 4.8g with a stock, white light with full polyp extension even though they have red bugs and are waiting for an interceptor delivery. Salinity is the only parameter I bother checking and it’s stability is easily one of the most important things to a successful tank imo.

 

[overhead]

I have a couple of cheap ATO's on my tanks. Pretty easy to figure out whether you "need" them or not, see how often you have to add water and calculate the cost of ATO vs the effort you put in to fill the tanks. I have enough stuff to do, I prefer to check with ATO container once a week vs checking the water level in the pump chamber every day.

 

[KrisReef]

I’m happy for mine. It’s a lot easier to have someone who is watching over the tank when you’re away to top off the ATO reservoir and if you have a huge reservoir it removes one of the likely causes for a problem, salinity is not unstable in the ocean and an ato can easily keep it reliably stable.

I have a 5 gallon bucket that gravity feeds a float switch in the sump. No electricity or sensors, just evaporation and gravity driven replacement, stable for years if I remember to keep the reservoir filled.

 

[JonoH]

Depends on the size of your tank.

A nano tank could get away with a gravity fed top off.

My tank is currently evaporating between 6-8L of water a day, I would consider this impossible to maintain without my ATO, as my pumps would run the sump dry.

 

[exnisstech]

6g with a lid I'd probably put a mark on the tank and keep a bottle of top off water nearby and pour it in as needed but I would probably do it daily. I imagine you could use your daily evap rate to calculate your salinity swing and decide how much of a swing your comfortable with and top off on a schedule as needed to keep you there.

 

[ccole]

I just add a couple gallons of RO water a night to my sump (system size 250 gallons). It doesn’t seem to really bother anything.

 

[larrysaltisfun]

I have a 240 gallon system. I just add RO water first thing in the morning when I feed my fish Nori I have a mark on the sump that I fill the water up to. It’s about a gallon and a half per day . everybody says you can’t live without it but I honestly don’t see the benefit because to me it’s like brushing your teeth. You just don’t forget to do it. I don’t have any SPS coral and I don’t know if the swings in salinity would be that dramatic by adding a gallon and a half to a 240 gallon system. Also Whenever I am home, I just check the tank a couple times a day and sometimes I add water 3 to 4 times. to me, it’s not a big deal.

But then again I’m the dingbat that used to drive 70 miles to another state to pick up 100 gallons saltwater every 14 days before I put in my own RO system. I’m kind of hardheaded.

 

[PolypPocket]

You guys are awesome, thank you for the feedback. Seems like it might be a good idea for peace of mind even if it’s not 100% required. Most of you seem to agree that you’re glad you have one.

I think I will try the one I linked, unless anyone has any other suggestions.

Thanks again!

 

[PolypPocket]

No it is not 100% necessary, but it is 100% worth it.

Ha, say no more

 

[PolypPocket]

An ato is important for stability especially in a small tank. I’m running a similar one as your link for 2 years it’s been pretty solid

Ok good to know the less expensive versions can work just as well, thanks!

 

[Gumbies R Us]

For me it’s 100% essential just because I travel out of town a lot. It gives me a peace of mind that I can travel, and not worry about my water evaporating

 

[exnisstech]

You guys are awesome, thank you for the feedback. Seems like it might be a good idea for peace of mind even if it’s not 100% required. Most of you seem to agree that you’re glad you have one.

I think I will try the one I linked, unless anyone has any other suggestions.

Thanks again!

Here a cheap one I've been running for over a year with no issues.
Link
My comments above were if I had a tiny tank with a lid. I run an ATO on all my tanks.