Low salinity: again! what am I doing wrong

[JAMreef]

I finished cycling a Red Sea reefer 350 several weeks ago. Currently I have a clean up crew and I added my starry blenny and brittle starfish from my other tank.

Before doing my first water change I noticed the salinity was very low, so I attempted to bring it back up slowly. I finally got it to where I wanted it but now after checking the salinity A week later I noticed it was super low again. The only thing that it must be is the ATO. What am I doing wrong? Am I not filling the sump back up fully? I checked my other tank and it is spot on so it’s not an issue with calibration.

I need to bring the salinity back up (currently at 26ppt). How can I do this without shocking tank mates? Also how can I prevent this from happening again?

 

[Luke’s reef]

If equipment is not an issues and you do not have massive hidden salt creep anywhere, I would have to either guess you ATO has put in to much Water into the tank Be it by pure evaporation or maybe a fluctuation of water due to sudden blockage of down pipes (snail stuck in overflow or something along the lines) which eventually released and went back to normal causing the change. Another way could be during your water changes maybe its not mixing properly (not saying you are not doing it right) but can happen, remember temperature plays a lot in how the SG reads in the tank so when changing water the temp must also be the same other wise you will be getting false readings and possibly unknowingly altering the SG.

Hope this helps and you sort the issue out, ill keep an eye out on your post see how it goes.

 

[JAMreef]

If equipment is not an issues and you do not have massive hidden salt creep anywhere, I would have to either guess you ATO has put in to much Water into the tank Be it by pure evaporation or maybe a fluctuation of water due to sudden blockage of down pipes (snail stuck in overflow or something along the lines) which eventually released and went back to normal causing the change. Another way could be during your water changes maybe its not mixing properly (not saying you are not doing it right) but can happen, remember temperature plays a lot in how the SG reads in the tank so when changing water the temp must also be the same other wise you will be getting false readings and possibly unknowingly altering the SG.

Hope this helps and you sort the issue out, ill keep an eye out on your post see how it goes.

I see what you mean about temperature changes. I use a thermometer to make sure they are close to the same temperature before I do a water change.

I wonder if I’m not filling the sump back all the way when doing water changes? I’ve tried looking up Red Sea to see if they have an exact level to keep the sump water but I have yet to find it.

Maybe you’re right about a snail getting stuck just wanting to be cautious since this is the second time this has happened.

 

[Luke’s reef]

I see what you mean about temperature changes. I use a thermometer to make sure they are close to the same temperature before I do a water change.

I wonder if I’m not filling the sump back all the way when doing water changes? I’ve tried looking up Red Sea to see if they have an exact level to keep the sump water but I have yet to find it.

Maybe you’re right about a snail getting stuck just wanting to be cautious since this is the second time this has happened.

Ok try this on your next water change, before you take any water out at all get some electrical tape and mark your current water level. Then when you do your change fill it to the same level, remember consistency is key in this game. There are many levels at which you can operate your sump what matters is you need to be very precise with how much water goes out and how much goes in, if you try to guess or gauge by eye you might be putting in less water that your taking out essentially lowering your SG slowly.

Alternatively you can use a container marked with Litres or gallons but ive found they are very unreliable so I use the tape system and have always maintained SG perfectly that way.

 

[swiss1939]

Taking a chance here, but are you closing off the ATO valve knob before you do water changes? Could be if its left open when you do water changes you are causing the whole ATO resevoir to dump into the tank and diluting your water. And make sure you refill the tank so the ATO float is high enough to be in the closed state when done with WC before reopening the ATO valve.

 

[Luke’s reef]

Also looking closely at your sump pic I think your water level is to high as its over the grated piece that divides the front and rear compartment, it should be flowing through the grate rather than over. Not a major issue Though but it helps control the water flow in your sump for when you have your skimmer.

 

[JAMreef]

Ok try this on your next water change, before you take any water out at all get some electrical tape and mark your current water level. Then when you do your change fill it to the same level, remember consistency is key in this game. There are many levels at which you can operate your sump what matters is you need to be very precise with how much water goes out and how much goes in, if you try to guess or gauge by eye you might be putting in less water that your taking out essentially lowering your SG slowly.

Alternatively you can use a container marked with Litres or gallons but ive found they are very unreliable so I use the tape system and have always maintained SG perfectly that way.

Okay I will try this. Such a simple fix for such a major issue! Thank you for your response

 

[Saltyreef]

100% agree with above comment

 

[Luke’s reef]

Taking a chance here, but are you closing off the ATO valve knob before you do water changes? Could be if its left open when you do water changes you are causing the whole ATO resevoir to dump into the tank and diluting your water. And make sure you refill the tank so the ATO float is high enough to be in the closed state when done with WC before reopening the ATO valve.

That could very well be true, I do not usually do Wc’s in my sump tho. I always turn all my pumps off let the sump fill up to avoid the ATO to dump its load into the tank while the change is being done then with a power head I kick up as much dirt as i can from rocks ect and syphon it out from the main tank.

 

[Cory]

Unless there is a leak there is never any reason for salinity to actually drop.

 

[smokin'reefer]

The only time I've experienced this on my reefer 450 I found a small leak under the weir. Might be a good idea to keep your eye out.

 

[JAMreef]

Taking a chance here, but are you closing off the ATO valve knob before you do water changes? Could be if its left open when you do water changes you are causing the whole ATO resevoir to dump into the tank and diluting your water. And make sure you refill the tank so the ATO float is high enough to be in the closed state when done with WC before reopening the ATO valve.

No, I haven’t urned it off. Honestly didn’t think I needed to if I was only pulling water from the display tank. The Red Sea reefer comes with instructions on how to put it together but not how to do proper water changes! I even tried watching YouTube videos on how to do water changes with a sump and ATO! Lol this is my first all-in-one tank so still getting the hang of this.

I feel like an idiot, that’s probably exactly what the issue is Lol! Thank you

 

[BeMoto]

What ATO are you using?

Edit: i didn't see the picture with the Red Sea top off setup.

Are you shutting the ATO valve befor doing a water change?

 

[JAMreef]

Also looking closely at your sump pic I think your water level is to high as its over the grated piece that divides the front and rear compartment, it should be flowing through the grate rather than over. Not a major issue Though but it helps control the water flow in your sump for when you have your skimmer.

Okay, I see that now. Wish I had come here and asked you guys questions weeks ago!

 

[Luke’s reef]

No, I haven’t urned it off. Honestly didn’t think I needed to if I was only pulling water from the display tank. The Red Sea reefer comes with instructions on how to put it together but not how to do proper water changes! I even tried watching YouTube videos on how to do water changes with a sump and ATO! Lol this is my first all-in-one tank so still getting the hang of this.

I feel like an idiot, that’s probably exactly what the issue is Lol! Thank you

Its ok, we were all beginners here at one point in life. But do some research into your tank on youtube and on R2R, quite a good selection of RS reefer builds here to help you.

 

[swiss1939]

Also, once you get your correct water level set up, if you are making minor tweaks to the return/overflow trying to dial in your overflow water height, you should close the ATO valve cause this will cause some drastic water level changes in the float chamber and can cause the ATO to dump water when not needed. Always close the ATO valve before doing anything that will affect water level.

 

[JAMreef]

The all in one that comes with the Red Sea 350.

 

[JAMreef]

Also, once you get your correct water level set up, if you are making minor tweaks to the return/overflow trying to dial in your overflow water height, you should close the ATO valve cause this will cause some drastic water level changes in the float chamber and can cause the ATO to dump water when not needed. Always close the ATO valve before doing anything that will affect water level.

Yes, yet another thing I was doing and not realizing it could cause a problem. Thank you all for your comments and help with this issue!

 

[wes urquhart]

I would start looking for a slow leak somewhere.

 

[Luke’s reef]

Also, once you get your correct water level set up, if you are making minor tweaks to the return/overflow trying to dial in your overflow water height, you should close the ATO valve cause this will cause some drastic water level changes in the float chamber and can cause the ATO to dump water when not needed. Always close the ATO valve before doing anything that will affect water level.

+1 on that, any changes you do with the flow valve make sure you turn that ATO off. Once you have it where you want it then you can adjust the valve accordingly to slowly drip back. Glad we are helping you get your tank done mate, remember even the most seasoned of aquarium keepers still make mistakes and still have things to learn. This hobby is constantly evolving and changing just enjoy it all you can and if in any doubt research and ask here