I have a 10 gal SW fish only tank with a damsel in it. I have one of those hang in the tank salinity meters that I figured would constantly monitor the salinity. Well acording to the gauge, when I first did my water change the SG was at the top of the scale even though I followed the directions on the salt. OK so I diluted it down over time to a normal level. Now I notice the SG is dropping almost daily. Where is the salt going? I have a HOB filter no LR or LS just regular aquarium gravel. The tank is cycled amonia 0, nitrites 0 and nitrates 10. With salt being a precipitate I wouldn't think it would just disappear and from what I have read, evaporation increases salt content so I don't get it.
Where is my salt going?
- Thread starter jas179
- Start date
look for a rim of salt either on your tank lip or around the filter. The only way you could loose salintiy would be through leakage . You are correct that it doesn't evaporate.
hth
Max
hth
Max
Missing Salt Theory
Is there any credibility to the idea of salt comming out of solution and settling in the substrate. This could in theory result in a lower reading on my gauge. Since I have a fish only tank with regular gravel rather than live sand or rock, the substrate is stagnant. I am only using a HOB filter rated for a 20 gal tank with no power heads or other additional means of water circulation. What do you think?
Is there any credibility to the idea of salt comming out of solution and settling in the substrate. This could in theory result in a lower reading on my gauge. Since I have a fish only tank with regular gravel rather than live sand or rock, the substrate is stagnant. I am only using a HOB filter rated for a 20 gal tank with no power heads or other additional means of water circulation. What do you think?
I don't see how it would be possible. It would be more likely that you had a salt crystal in the hydrometer or that your temp was way off. The relationship to salinity and temp are non-linear.
Sorry
Max
Sorry
Max
to be able to have salt form a pervepitate, you would literaly need more salt molecules than water technicly. salts such as NaCl (table salt and what makes up most of the salt in sea water) is able to dissolve in water because of the intermolecular forces. If you would really like me to eleborate more on that i would probably have to write at least a page explaining everyting, if you want me to, i dont mind because i like chem. lol. But i doubt many people will read it/care. lol but to sum it up, each ion of a salt is attracted to either the oxygen (if it is positive) or the H (if it is negative) on water much like a positive and a negative owuld attract on a magnet. But since bonds are not actualy formed, they just stick to it basicly, many many ions can still to each atom of a molecule of water. so you would have to have a LOT of salt compared to water. much more than ocean levelsjas179 said:
i would aslo suggest the salt creep
it sounds like you are usuing a hydrometer. are you sure there were no bubbles that are dissapearing?
or even more likely, as your water level decreases, are you making sure that the water level on the hydrometer is where it is suposed to be? are you moving that down along with it?
fishieness said:
Thanks for reminding me of my chemistry. You are right. As for salt creep, I do not notice much salt around the rim of the tank. The hydrometer is actually totally submerged to about the middle depth of the tank. Temperature could be an issue since the tank is not heated. Due the cold nature of the rest of the inhabitans of the house, the room temp tends to run about 77 degrees.
what does the tank run at?
is it a constant temp?
i dont believe your mydrometer should be running at about mid-depth. look at it and there is probably a line where the waterline is suposed to be.
is it a constant temp?
i dont believe your mydrometer should be running at about mid-depth. look at it and there is probably a line where the waterline is suposed to be.
If you can find a LFS that has a refractometer to measure your salinity take a water sample to them next time your in doubt. I never trusted the idea of those leave in hydrometers---like others have said--bubbles, needle sticks, etc. Heck--I really don't trust my take out hydrometer. I clean it with warm water every time I use it. I never get the exact same reading--always 1 point off at least.
The first time I had my water tested at my LFS it was 1.023 on the refractometer and my hydrometer was reading 1.020.
Anyway---your SG is probably more stable than the hydrometer reads, but it's best to verify it.
The first time I had my water tested at my LFS it was 1.023 on the refractometer and my hydrometer was reading 1.020.
Anyway---your SG is probably more stable than the hydrometer reads, but it's best to verify it.
I used one of those hang in tank meters too. Big mistake. They get dirty and just the weight of sediment will make it seem you are losing salt. By the time I realized what the problem was I had added so much new salt water that i had to dump about 20 gallons of water. What a waste. Threw the dang thing out and ust the old method and no problem since. I have a 75 gallon.