Acceptable daily salinity swing

[PDR]

I am having to manually top off one of my tanks for now and was wondering what is considered the maximum acceptable daily salinity swing. And by acceptable, I don't mean that the system will survive it, but more or less not notice it.

Thanks

 

[DEWreefing]

I swing up to .001 point with tempature swings.
1.025 to 1.026

 

[laverda]

I have never track the changes in day, but I know your fish should be able to handle pretty big swings as the salinity can change significantly in the Oceanus to underwater springs, storms and runoff.

 

[PDR]

I should have explained this in my original post, but I am, unexpectantly, having to go out of town for about a week and will not have a chance to get my ATO up and running before I leave. I have a tank sitter coming every other day and am trying to determine if 2 days of evaporation would cause too much of an issue.

Testing over the last couple of days seems to result in an evaporation rate of about 1/2 gallon per day on a minimum of 35 actual gallons. Using a calculator online, it seems that 1 gallon of evaporation should only change the salinity by .0008.

I know the fish can handle it fine, but what about other inverts and coral?

 

[LobsterOfJustice]

It takes a lot of evaporation to noticeably change salinity. Topping off every other day should be fine. Luckily, things handle a quick drop in salinity (like dumping in a gallon of fresh water to replace several days worth of evaporation) better than they handle quick increases, and the evaporation will happen slowly and consistently.

 

[DEWreefing]

On my 220 total gallon system I can go through a lil over 5 gallons. When my ato quit working my tank shot up from 35ppt to 38ppt while I was out of town. I lost like 4 sensitive acroporas.

 

[jdpeters]

I know this is old but I had my dad watch my tank when me and my wife were on vacation. It went 7 days without being topped off and heater became exposed. Everything lived. Speed forward to yesterday my ato dumped about 3 gallons into my display and after checking the salinity it was at 1.024-1.025. I try to maintain 35ppt. Not sure how bad my salinity was to begin with. I check with a hydrometer and I think they are realitively accurate but the community is generally not a big fan. The same time my heater went on the fritz and brought my tank up to 82. I pulled it out and put in a small replacement which overnight dropped it down to 76.1. I hope my tank looks fine when I get home lol

 

[juanxchoreef]

I swing up to .001 point with tempature swings.
1.025 to 1.026

Hello, does it mean that at higher temperatures density is lower? because im reading 1.024. It was at 1.025

 

[Randy Holmes-Farley Verified Community Expert]

Hello, does it mean that at higher temperatures density is lower? because im reading 1.024. It was at 1.025

Density is lower at higher temps, but salinity is unchanged and specific gravity hardly changes at all with temp changes.

 

[BryanM]

I should have explained this in my original post, but I am, unexpectantly, having to go out of town for about a week and will not have a chance to get my ATO up and running before I leave. I have a tank sitter coming every other day and am trying to determine if 2 days of evaporation would cause too much of an issue.

Testing over the last couple of days seems to result in an evaporation rate of about 1/2 gallon per day on a minimum of 35 actual gallons. Using a calculator online, it seems that 1 gallon of evaporation should only change the salinity by .0008.

I know the fish can handle it fine, but what about other inverts and coral?

I personally think you'll be just fine.

 

[Borat]

0.0000001 is acceptable

 

[juanxchoreef]

Density is lower at higher temps, but salinity is unchanged and specific gravity hardly changes at all with temp changes.

I definitely did something wrong then. I will do a small waterchange tomorrow to rebalance the system

 

[Randy Holmes-Farley Verified Community Expert]

I definitely did something wrong then. I will do a small waterchange tomorrow to rebalance the system

So what I gave is a technical answer, but how you measure salinity is unlikely to give density. How are you measuring salinity?

 

[juanxchoreef]

So what I gave is a technical answer, but how you measure salinity is unlikely to give density. How are you measuring salinity?

i do test salinity with the classic refractometer.

 

[Randy Holmes-Farley Verified Community Expert]

i do test salinity with the classic refractometer.

An ATC refractometer should give an answer largely independent of the water temperature.

 

[juanxchoreef]

An ATC refractometer should give an answer largely independent of the water temperature.

Thats kinda weird then. Because this week i noticed masive sps growth, nothing like before. The tank is young. May the trace elements lower the salinity readings?

today parameters:
dKH 8.4
Cal 430
Mg 1440

Im dosing 3 part from ASF Aquarium System from France. kh and ph buffer, Calcium and Stroncium buffer, Magnesium (not adding at the moment) and a third part which contains Calcium, magnesium, strontium & carbonates, with the addition of potassium, bromine and iodine in the unique ratio required by corals.

In addition i double checked the ROI water reservoir i case it mixes slowly with the sump water. And the reservoir its 0005ppm

 

[juanxchoreef]

it may be nothing but its improving. This acro that i bought had RTN and after 5 months it's better.

1 and 15 days between pictures

 

[Randy Holmes-Farley Verified Community Expert]

Trace elements by definition have no impact on salinity.

 

[Randy Holmes-Farley Verified Community Expert]

with the addition of potassium, bromine and iodine in the unique ratio required by corals.

Um, that’s marketing lingo, not something supported by actual evidence.

 

[juanxchoreef]

Um, that’s marketing lingo, not something supported by actual evidence.

I assume that, i wouldn't buy the brand again, its working by the moment. But LFS sold me this instead Tropic Marin balling system, basically they've sold me a dud. Anyways here in Buenos Aires the temp is cooling down so i will check salinity with the temp at 25 celsius