Hyposalinity - How to safely raise levels

[dimik]

When treating via hyposalinity at 1.009 what is the safest way & time frame to raise levels?


If I'm running hypo in a 20G tank how much water should I remove & exchange with higher salinity water?

How often should I change out the water?

What should the salinity of the new water be when adding it to the hypo water to maintain a steady balance?

What is a safe rate of salinity increase per day?

I've read multiple guides and people saying to raise it slowly but, noone gives details as to what slowly is.

 

[canadianeh]

how about dropping the salinity or when bring new fish from LFS? Do we put the fish into QT tank with normal salinity 1.026 and then slowly bring it down to 1.009? OR, do we drip acclimate the fish to 1.009 right away?

 

[ichthyogeek]

No idea, but I know that rotifers can withstand specific gravity changes of .005 every 24 hours. So assuming that fish (which are much hardier) have similar requirements to rotifers when it comes to specific gravity changes, you can probably say you can raise the SG of the tank by .005 SG every 24 hours. Assuming you're aiming for a SG of 1.026, that's a .017 SG change. This translates to around ~3 days of changing the salinity. Let this be the minimum amount of time for you to raise your tank's salinity.

BUT remember that there's a lot of dilution going on. Raising your tank's SG from 1.009 to 1.014 will require you to change out 6 gallons of water at first. But when you want to raise the tank water to 1.019, you'll need to change out 9 gallons. To get to 1.024, you'll need to change 15 gallons...

What may be better, is for you to continue doing your weekly water changes of around 25% or so. Here's a nice table for you to see what happens over time, assuming a 25% water change (5 gallons) each week (rounded to the nearest .001):

Week	SG
1	1.009 (no WC)
2	1.013
3	1.016
4	1.019
5	1.021
6	1.022
7	1.023
8	1.024
9	1.025

For bringing in new fish from the fish store, get them to the store's parameters, then drop the SG accordingly.

 

[Drew1900]

Here’s a calculator that does everything for you https://www.saltyzoo.com/SaltyCalcs/SalinityAdjust.php

 

[dimik]

No idea, but I know that rotifers can withstand specific gravity changes of .005 every 24 hours. So assuming that fish (which are much hardier) have similar requirements to rotifers when it comes to specific gravity changes, you can probably say you can raise the SG of the tank by .005 SG every 24 hours. Assuming you're aiming for a SG of 1.026, that's a .017 SG change. This translates to around ~3 days of changing the salinity. Let this be the minimum amount of time for you to raise your tank's salinity.

BUT remember that there's a lot of dilution going on. Raising your tank's SG from 1.009 to 1.014 will require you to change out 6 gallons of water at first. But when you want to raise the tank water to 1.019, you'll need to change out 9 gallons. To get to 1.024, you'll need to change 15 gallons...

What may be better, is for you to continue doing your weekly water changes of around 25% or so. Here's a nice table for you to see what happens over time, assuming a 25% water change (5 gallons) each week (rounded to the nearest .001):

Week	SG
1	1.009 (no WC)
2	1.013
3	1.016
4	1.019
5	1.021
6	1.022
7	1.023
8	1.024
9	1.025

For bringing in new fish from the fish store, get them to the store's parameters, then drop the SG accordingly.

Thank you for your input. I'll aim for a .005 increase per day.

Here’s a calculator that does everything for you https://www.saltyzoo.com/SaltyCalcs/SalinityAdjust.php

Thanks I use this calculator too but It doesn't tell you how long to wait until the next water change. That's my Q / issue. I don't want to move too fast.