Salinity Swings

I was just wondering what you all thought about salinity swings as a result of evaporation and then the resulting water replenishment every couple of days. What are you opinions as far as stressing corals, inverts, and fishy's. Right now my swings from about 1.023-1.025 Thanks for the input.

 

Dh , your slainity swings can come from 2 things,

1, when doing water changes always pull of the same amount of water that you plan on putting back in.
( example: 5 gallons removed , replenish 5 gallons. )

2, when water evaporates from your total sum of water , Usealy noticible from the level in the sump ( i have a mark in the sump where i like to keep the water level )
(example: if water has evaporated from the sump, add back the same amount of RO/DI
water ONLY.)

Reason being the water that evaporates from your tank is plain water , the salt remains.
If you remove water intenionaly for water changes , you are removing salt along with it.

make sure when you do water changes that you check salinity first , if it reads 1.025
before doing a water change , then have your make-up water read exactly the same.
thereby keeping salinity the same as where you had it.

If you wish to increase salinity , then increase it,adding more salt to the make up water slowly raising it over the course of a few days.
If you want to reduce the salinity then you add less salt to your make up water by a couple of points ( over time and sevral water changes ).

Also making up your change out new water it's suggested that you make it then let it set over night or atleast a few hours to give the new water and the salt in your make up tank/bucket time to disolve.
if you added to much salt to your make up water , then it will be much easier to correct then and alot safer
either by adding water or salt to get the desired targeted salinity.

I dont suggest in making salinity changes in one huge water change,
Most fish don't like that and Corals definently don't.
Your best off keeping the salinity as stable as possible.

 

Thanks for your info, and trying not to sound like a smartass I did know all of that. My main question relates evaporation, unless I'm adding water everyday after 2-3 days I'll have a great deal of evaporation with my lighting and having an open top. Also I was trying to get at if a .002 swing is that detrimental. Thanks again

 

No problem Dh I did not know if you knew or not.

And the ansewer to a .002 swing>

You'll get quite of few opinions on that i should think,
And no i don't think a .002 is a large swing ( depending on the total body of water and what exactly your keeping in the tank )

I would say in a 5 gallon nano tank , it might hurt somthing really quick . beacuse the salinity changed so fast.

In a large tank like a 100 gallon or so , no it wouldint have as much an adverse effect on things ( it will take longer to mix all that water up and settle over a longer time frame )

 

Do you notice any ill-effects on your fish and coral when you refill is probably the first question to ask. It's probably not the worst thing in the world, but if you're worried about it, you could always use an auto-topoff system to continually replenish the evaporated water.

I'm working on a 'bucket type' auto-topoff system for my new tank, though I'm sure someone has already invented such a thing. If not, I'll share schematics when I've completed them.

 

every tank is a little different but i notice a change in my corals in my 55 gallon tank after about 4 gallons of evaporation but not real bad.i also have a 29 gallon sump 3 quarters full

 

I haven't seen any changes really when it comes to anything in my tank. The only thing concerning me was the effects that I'm not noticing.

 

I have to put a gallon into my tank a day. I do a half gallon every 12 hrs or so and never have salinity swings but thats really babying the tank i guess

 

Otty did a real cheap, easy auto top off for his QT tank that I'm thinking of doing with a trash can. I'm sure that if you sent him a PM he would share what he did with you no prob. I also allow my salinity to swing .002, everything is fine. The auto top off is an easy way to 1: cure this problem and 2: make things a lot easier on ya.