Salinity Calculations

[kiwis]

So I've been running my tank a while now, done 2 water changes no issues. My salinity is slightly on the high side when evaporation occurs.

So it's about 1.024 after maintenance but can slip as high as 1.025 and worst case 1.026 after a few days. I'm happy to keep on top of water top ups but really want to reduce it to 1.022

So tomorrow I'm looking to do a 10L water change (120L system).

How does everyone work it out? Normally I match my new water with old water.

I guess I want to slowly add 10L of new water with 1.015 (a guess) or something? or is there a better way to reduce this?

 

[Crabs McJones]

So I've been running my tank a while now, done 2 water changes no issues. My salinity is slightly on the high side when evaporation occurs.

So it's about 1.024 after maintenance but can slip as high as 1.025 and worst case 1.026 after a few days. I'm happy to keep on top of water top ups but really want to reduce it to 1.022

So tomorrow I'm looking to do a 10L water change (120L system).

How does everyone work it out? Normally I match my new water with old water.

I guess I want to slowly add 10L of new water with 1.015 (a guess) or something? or is there a better way to reduce this?

Any particular reason you want to lower it? 1.026 is actually the ideal number for reef tanks. But best way would be to take small amounts of saltwater out and replace it with freshwater, or do a series of water changes with the salinity slightly lower than where you want it until you hit the number you're looking for

 

[Diesel]

So why you think 1.026 is way to high?

 

[PDR]

+1 Nothing wrong with 1.026, that's where I run my tanks. I think the easiest way would be to remove some salt water and replace with RO vs trying to dilute it with a lower salinity.

 

[GoPitt88]

Yeah, not sure why you think 1.022 would be best. That being said, as they mentioned above, just take out some water from the tank and replace it with fresh RO water. Don’t over complicate it I’d start with a couple cups first, then measure the salinity. That will give you an idea of how much you’ll need to do. I’d go slowly too. Not too fast. You don’t want to stress the fish.