Salt Consumption

Warr7207

Moorish Idol
Joined
28 Dec 2007
Posts
12,781
Reaction score
31
Location
JHB
I have been running my tank for 4 months now and have noticed that no salt gets consumed.

What I am saying is my water changes are done at 1.025 and my top up's are RO water (no salt), and the SG level never drops. This indicates that no livestock consumes salt or whatever compounds constitute the SG level of the water ?

Is it heavily sps coral stocked tanks that consume "salt" ?
 

Alfie

Hawkfish
Joined
5 Oct 2007
Posts
1,607
Reaction score
14
Location
Cape Town
Warr no salt is consumed by any livestock in the tank. When the water evaporates the salt remains and should you not use top up water the sg will jump up. The addition of RO allows your sg to remain constant. Hence when you do a water cgange you take out water that has an sg of say 1025 and replace the same volume of water with an sg of 1025 thus remaining at 1025.
 

gaz19

Wrasse
Joined
10 Jun 2007
Posts
1,783
Reaction score
10
Location
durban,kloof
but, when your skimmer skims alot, some salt water is removed and is then replaced by RO water(via top up unit). over along period of time the SG can drop if not monitered.
 

Warr7207

Moorish Idol
Joined
28 Dec 2007
Posts
12,781
Reaction score
31
Location
JHB
Heavy Skimming uses up salt.
I skim as heavily as possible without actual water flowing into the cup. I also have an "overkill" skimmer for my volume of water - DNW200 for 400l
 

Rory

Admin
Joined
5 May 2007
Posts
4,857
Reaction score
37
Location
JHB
The volume of the stuff that isn't consumed that makes the water salty (sodium chloride) far outweighs the volume of the "useful" stuff that is consumed (all the other elements we supplement).

If your salinity is 35ppt (around 1.024) then most of those "parts" are sodium chloride (just salt). About 1.35 of those parts would be magnesium (at Mg = 1350ppm), 0.4 or so being Ca, 0.2 being CaCO3 carbonate alkalinity and even less of everything else.

So if somehow your corals etc managed to absorb every bit of calcium and every other trace element until everything tested 0 your total salinity would probably drop to 1.023 from 1.024 or something.

Putting in supplements also of course raises your salinity but you're very unlikely to be able to detect a change because it will be so small.
 

Rory

Admin
Joined
5 May 2007
Posts
4,857
Reaction score
37
Location
JHB
I skim as heavily as possible without actual water flowing into the cup. I also have an "overkill" skimmer for my volume of water - DNW200 for 400l
That's not overkill at all! :p
 

Warr7207

Moorish Idol
Joined
28 Dec 2007
Posts
12,781
Reaction score
31
Location
JHB
That's not overkill at all! :p
Cool, so the the actual salt level not changing is really a normal part of the tank's life. Need to watch the other elements that the corals consume.

Thanks
 

Rory

Admin
Joined
5 May 2007
Posts
4,857
Reaction score
37
Location
JHB
Yep. You should always check to be sure etc as skimming and salt creep does lower salinity so you might have to do your next water change with a slightly higher salinity etc.
 

Warr7207

Moorish Idol
Joined
28 Dec 2007
Posts
12,781
Reaction score
31
Location
JHB
Yep. You should always check to be sure etc as skimming and salt creep does lower salinity so you might have to do your next water change with a slightly higher salinity etc.
I always check, me and my kids love using the refractometer :p
 

Similar threads


Top