Tank Cleaning

[Epicanimal]

I was just wondering what the salinity of your prepared water should be before adding it to your tank.
Please help.

 

[Taxus812]

A bit to vague to answer directly. If you want your salinity at 35ppt then your new water should be the same. If it is lower than desired there are calculators that will tell you what to mix up to bring you tank to that level.

What is your tank at now? What type of tanks do you want? (Fish only, mixed reef etc)

 

[Epicanimal]

I have a reef tank. Basically when the tank is full its at 35 ppt but if you are changing it and take out lets say 5 gallons what should be the amount of salt in the new water you added.

 

[Taxus812]

If you want to stay at 35ppt. You should also mix your 5gal of saltwater for your water change so it is also 35ppt. (Following the manufacturer instructions). The volume does not matter. If you changed 40gal and wanted to stay at 35ppt then the new water would be mixed to 35ppt and then added to your tank.

It’s only when you want to increase or decrease your salinity that you start to muck about with mixing the water at a different salinity.

34- 35ppt is a pretty standard salinity for a mixed reef in case I totally misread your question.

 

[Epicanimal]

Really thanks. I thought that taking water out would increase the salinity though

 

[Auquanut]

If you're asking how much salt to add to your RO to match your tank water, I always initially add a little less than what I think is right, and test. Then add a little bit more to match the tank. That way, if I'm wrong, it's easier to add more salt than more RO. It doesn't have to be dead on. If you're doing a 20% water change and your new water is 36 ppt, the total change to the tank is only .2 ppt different. Your tank won't notice the difference. Unless my math is wrong.

 

[Auquanut]

Replacing salt water with the same salinity water won't raise the salinity. Just be sure you're topping off evaporated water with RO/DI.

 

[Epicanimal]

Thanks so much

 

[Taxus812]

Really thanks. I thought that taking water out would increase the salinity though

Only through evaporation. When water evaporates it leaves the salts behind yielding a higher salt to water ratio (an increase salinity ). When you remove water with let’s say a bucket, you pull both water and salt out in the same proportions. So you have less volume but the salinity remains unchanged.

Hope this makes sense.