specific gravity help

[Mach]

Hey everyone,

I am having trouble keeping my specific gravity stable. I try to keep it around 1.025 - 1.027. My water seems to evaporate at an incredible rate also. I have not been able to find out why either. But for some reason, my specific gravity increases towards 1.029. When I do my topoffs, I use freshwater thinking that it will decrease the SG. It seems to work, but the next day it rises back up. I usually lose over a gallon of water a day. I run my lights about 6 hours a day. I have a glass hood over my tank with T5 lighting. I run my sump with an insump skimmer. I also am running an canister filter right now. The only thing in my tank is a 5-6" live sand bed and 160lbs Liverock. I am also running four maxijet 900.

My questions are,
Why does my SG keep rising? How can I maintain it? And how can I stop my water from evaporating so quickly?


Thanks In Advance,
Anthony

 

[Biggen]

This is a 90 gallon tank, correct? I find it hard to believe that the SG can vary so much in such a large tank. 1 gallon of water evaporating a day is not that much at all. I have a 40 gallon and mine evaporates 1-1.5 gallons of water a day and I don't have large SG swings like this.

What are you using to measure you SG with? Swing arm hydrometer? Floating glass hydrometer? Refractometer? Just wondering how accurate your measuring device is.

FYI, I use a dripper to maintain the proper SG in my tank. I simply have a suspended doser hung above my sump. Airline tubing runs from the doser to the water level right above the sump and drips in continuously. I just refill the doser every day to every other day with RO water.

 

[SquishyFish]

I have to agree w/ him. I put 5 gallons of water in my sump every few days to top off the evaporation. I am going to start using a DYI drip system this week that I just finished testing.

What you will need.
A rinsed milk jug
airline tubing
silicone

Take a nail or a drill and put a hole in the lid of the jug just big enough to feed the air line tubing through. Poke a small hole near the top of the jug to allow it to breathe. Feed the line to the bottom of the jug. (if you are using this to drip kalk, dont go any lower than half way down.) Use the silicone to secure the hose into the lid. Run the line into the sump and tie a knot in the line to adjust the flow rate.

Basically your adapting the "drip system" of acclimating fish to replace the evaporation of your tank. Its not as sophisticated as a professional top-off system, but it also will not flood your tank.

Squishy

 

[Mach]

yes its a 90g . I am using a refractometer. And when i make up my water I get it to the SG that I want. I let it sit overnight with a powerhead and heater, then do my water change. The next day the SG is good, then by the third day it creeps up. Im guessing due to the water evaporation. But by toping off with freshwater, I figure it would lower the SG back down.

Im gonna try your drip system, perhaps keeping the water level the same always will fix my SG problem.

This hobby is very stressful for a newbie like me. For every action, there is a reaction. But whenever I see a matured tank, I know its worth it cause someday mine will look like that. ( I hope)

 

[SquishyFish]

I would think you could adapt the drip system to a 5 gallon bucket if you have the room under your tank. I just thought of that...but i bet it would work.

Squishy

 

[Bang Guy]

If you have a refractometer why are you listing S.G.? You should be using the Salinity side of the scale. Shoot for 35ppt. other than that I agree with the previous posters. Just replace evaporated water with RO/DI water and everything should be fine.