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Water evaporation in BW
Posted: Mon Mar 27, 2006 8:23 pm
by kass
I am assuming (correct me if I am wrong) that when water evaporates from a BW tank, it would cause the SG to rise due to less water with the same amount of salt. Is the best way to deal with this to top off the tank with FW and only add more BW when doing water changes?
Posted: Mon Mar 27, 2006 9:51 pm
by The Fisherman
well, the short answer is: Yes.
the long answer: in a BW tank, when water evaporates, the SG rises ( although in a brackish tank its not going to be too bad) , so I top off the tank with FW every 3 days or so, ( using RO for this is really good too). then when i do a WC your obviously removing BW, so i replenish with BW of the same SG.
Posted: Tue Mar 28, 2006 5:26 am
by saffib
Condensation trays on top of the tank should preven this becoming a problem. I never top my tank up, with weekly water changes and well-cut condensate trays, I don't find this a problem. If anything, I would get the opposite effect with saltcreep!
Posted: Tue Mar 28, 2006 12:41 pm
by kass
The tank is a mudskippper tank and only has about 3 inches of water and I try to keep it really humid for them. Atleast 1/3 of the water evaporates each week.
Posted: Tue Mar 28, 2006 1:47 pm
by Pufferpunk
I would just top it off then. What SG are they at? Aren't you doing water changes on that tank? I'm waiting for 1 frog to find a new home & then it's skippers for me!
Posted: Tue Mar 28, 2006 2:00 pm
by kass
Its at 1.008. Yeah I change 50% weekly. For a while, when I did a water change, I would take out whatever and then just add more BW to make up for the evaporation. But I noticed that the SG was rising quite a bit, so then I just started adding FW to make up for the evaporation, and cary out normal water changes.
Posted: Tue Mar 28, 2006 2:47 pm
by Pufferpunk
Is that the proper SG of those guys?
Posted: Tue Mar 28, 2006 3:43 pm
by kass
I was planning on keeping it around 1.005, I read that they do well at that level
http://members.ozemail.com.au/~thebobo/care.htm.
But it rose quite a bit from my confusion with the evaporation. It was actually up to 1.012 and now I'm bringing it down slowly. They seemed fine at that SG though. I know they can withstand large changes in SG, but I'm sure its not good for the nitrifying bacteria.
Posted: Tue Mar 28, 2006 5:35 pm
by Pufferpunk
This is where mine will be going:

Perfect for skippers, huh?
Posted: Tue Mar 28, 2006 5:37 pm
by kass
Yeah that looks awsome. How big is the tank? What did you use to keep the gravel held up to make the land area?
Posted: Tue Mar 28, 2006 6:44 pm
by Pufferpunk
55g. It's a river tank kit where you silicone in the pieces.
Posted: Tue Mar 28, 2006 8:05 pm
by kass
Oh cool. I have tried to make land areas with not much success. I recently had a tank divider that went around 3 inches high and i filled it up with gravel and topped it with sand. But I just removed it the other day because the skippers stopped going on it.
Posted: Tue Mar 28, 2006 8:07 pm
by The Fisherman
hmmm, ill have to try something like that whenever i get around to doing the mini-crab setup ive been wanting to do.
Posted: Tue Mar 28, 2006 8:37 pm
by kass
When I upgrade my tank this summer I think I might get a fidler crab.
Posted: Tue Mar 28, 2006 8:40 pm
by The Fisherman
will the crab be in with the skippers? im not sure theyll play too nice.