Questions about auto top off.

Nalchadz

New member
Hello Everyone, I have a couple of questions regarding an auto top off system. I am trying to decide if I need one or not. Currently I do weekly water changes. I use Real Ocean water which I purchase from my LFS. Every Sunday morning I take out about 10 percent of the water in the tank and refill from my bucket. My salinity level is at 1.025 and has only been off by .001 once in the last few months. I use a Extech RF20 Portable salinity refractometer to check. That said, I am worried that something could go wrong at some point. I am thinking about purchasing an auto top off system. My tank is a 29 Gallon biocube. here are my questions.

1. Is it possible that the auto top off system may possibly drop the salinity level to much since I purchase Real Ocean water and don't mix the salt myself?

2. Do I need 2 auto top off systems? one with fresh water in the container and one with salt water in the container?

3. Or should I just keep doing what i've been doing and not worry about purchasing an auto top off system?
 
Your top-off water should be pure water. There's no need to add salt unless you are trying to raise the salinity in the tank.

Your top-off shouldn't negatively impact salinity unless it gets stuck on for some reason. There should be a float switch or something to make sure it only delivers as much as the tank needs.
 
As mentioned, the primary purpose of the top off is to replace straight RODI water that evaporates from the tank (leaving the salt behind) which would slowly raise the salinity in your tank.

What are you using now to top off the tank between your weekly water changes? Are you saying that at the end of a week, you haven't topped off with water and the salinity hasn't changed (at least measurably)? If that's the case I'd be surprised since it's only 29 gallons total.

Anyhow, stability is the name of the game in saltwater/reefs so you can do 1 of 2 things. 1) you can top off by hand to ensure the salinity stays consistent or 2) use an auto top off to do the same thing.

The auto top off doesn't really factor into the frequency of your water changes, so you can do those on whatever schedule works for you.
 
Okay, so I can add the auto top off system and at the same time continue my weekly water changes?

Yes, just be sure you turn off the ATO when you are doing your water change ;)

As mentioned, the primary purpose of the top off is to replace straight RODI water that evaporates from the tank (leaving the salt behind) which would slowly raise the salinity in your tank.

What are you using now to top off the tank between your weekly water changes? Are you saying that at the end of a week, you haven't topped off with water and the salinity hasn't changed (at least measurably)? If that's the case I'd be surprised since it's only 29 gallons total.

Anyhow, stability is the name of the game in saltwater/reefs so you can do 1 of 2 things. 1) you can top off by hand to ensure the salinity stays consistent or 2) use an auto top off to do the same thing.

The auto top off doesn't really factor into the frequency of your water changes, so you can do those on whatever schedule works for you.

For a Biocube that really isn't all that surprising since it has a hood. I hardly ever had to top off my 14g Biocube when it had the hood on....the minute I went topless the evaporation increased greatly and I had to do an ATO.
 
Questions about auto top off.

Do tanks with hoods and zero evaporation suffer from lack of oxygenation? Do fish gasp for air in covered tanks like the Biocube?

If evap is non-existent, then we can assume that gas exchange also is non-existent. Right?
 
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As mentioned, the primary purpose of the top off is to replace straight RODI water that evaporates from the tank (leaving the salt behind) which would slowly raise the salinity in your tank.

What are you using now to top off the tank between your weekly water changes? Are you saying that at the end of a week, you haven't topped off with water and the salinity hasn't changed (at least measurably)? If that's the case I'd be surprised since it's only 29 gallons total.

Anyhow, stability is the name of the game in saltwater/reefs so you can do 1 of 2 things. 1) you can top off by hand to ensure the salinity stays consistent or 2) use an auto top off to do the same thing.

The auto top off doesn't really factor into the frequency of your water changes, so you can do those on whatever schedule works for you.


I have not been doing any auto top off and its been a consistent 1.025 or 1.026. I even took the water to the LFS and they checked and confirmed.
 
Yes, just be sure you turn off the ATO when you are doing your water change ;)



For a Biocube that really isn't all that surprising since it has a hood. I hardly ever had to top off my 14g Biocube when it had the hood on....the minute I went topless the evaporation increased greatly and I had to do an ATO.


Yep, Mine has the hood and I haven't really noticed a lot of evaporation.
 
Thanks everyone! as always everyone here is AWESOME!

Do you guys have any recommendations of which Auto Top Off system I should get? Seems like Tunze is the way to go.
 
I have both a Apex controlled ATO for my display and a Tunze ATO for my frag system. For simplicity with several added safety features you can not beat a Tunze ATO system.

Mark
 
If you aren't getting any evaporation I would just manually top off as needed. That's a lot of money for something that will do nothing since there is no evaporation. Just make sure when you do top off for evaporation you don't use saltwater.
 
Do tanks with hoods and zero evaporation suffer from lack of oxygenation? Do fish gasp for air in covered tanks like the Biocube?

If evap is non-existent, then we can assume that gas exchange also is non-existent. Right?

Not necessarily. There is probably evaporation but it is condensating on the sides and top of the glass and dripping back into the tank essentially topping itself off with its own evaporated water. I would however be somewhat curious as to how enough fresh oxygen gets into the hood unless it is sufficiently replenished through holes in the back or when the hood is opened. I'm sure it gets in there some way or else people would have major problems with these tanks long before now, I just don't know where from.

Do these tanks use some sort of air pump in them anywhere that pulls air from outside of the tank?
 
If you aren't getting any evaporation I would just manually top off as needed. That's a lot of money for something that will do nothing since there is no evaporation. Just make sure when you do top off for evaporation you don't use saltwater.

Agreed, I didn't realize you weren't topping off manually now...so yeah..if it's stable and no topoff is needed, auto-topoff doesn't get you any real advantage.
 
Not necessarily. There is probably evaporation but it is condensating on the sides and top of the glass and dripping back into the tank essentially topping itself off with its own evaporated water. I would however be somewhat curious as to how enough fresh oxygen gets into the hood unless it is sufficiently replenished through holes in the back or when the hood is opened. I'm sure it gets in there some way or else people would have major problems with these tanks long before now, I just don't know where from.

Do these tanks use some sort of air pump in them anywhere that pulls air from outside of the tank?

Sorry for the late response. The hood has some air vents, also, my LFS told me to point the nozzle from the return pump up which will bring in Oxygen. There are no air pumps in the tank.
 
I recently started leaving the hood feeding door open because it gets hot due to the hot weather and have noticed the salt levels rise. I have been using RO to keep the level at 1.024. So far I have not had any issues.
 
I recently started leaving the hood feeding door open because it gets hot due to the hot weather and have noticed the salt levels rise. I have been using RO to keep the level at 1.024. So far I have not had any issues.

If it works then it works.

Until you grow weary of manual top offs.
:fun2:
 
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