Hey Everyone, I just started my first tank. Its a 50 gallon 36x18x18. When I was researching for getting started I read that coral like water of 1.025. When I mixed my water I made it exactly 1.025 when the tank is full of water. My water evaporates around 2 gallons a day. In the evening my tank reads 1.027 on my refractometer and then 1.025 when I top my tank off. Is my salinity too high or is this good? I'm thinking maybe I need to be around 1.022 so that when I evaporate my reading is around 1.025. Advice?
Evaporation Question
- Thread starter VtecGuy88
- Start date
ReefkeeperZ
New member
1.027 is fine and safe but rapid changes is what you don't want, from jumping from 1.025 to 1.027 and back every day is pretty big swings rapidly. I would look into some way to top off steadily through out the day to prevent such rapid swings.
crawlerman
Member
For now you could add a gallon in the morning and then another at night. But as everyone says, you want an auto top off. I went about 5 years before I got one and it is now one of my favorite pieces of equipment. I fill my reservoir once per week and I know my salinity is perfectly steady. I also add my buffer to the ATO reservoir so my alkalinity stays steady as well. This is important once you start adding coral. The steadier you can keep your water chemistry, the better your corals will do. It is not just salinity that changes with evaporation, concentrations of everything in the water change as well. I'd also recommend you get one with a sensor vs a switch. The switch requires more maintenance and can stick.
mcgyvr
New member
Simply set your pre-evaporation salinity to 1.024
Then with 2 gallons of evap it will be 1.025 which is totally acceptable..
I assumed approx 40gallons of actual water in your tank.
https://www.hamzasreef.com/Contents/Calculators/ResultingSalinity.php
Then with 2 gallons of evap it will be 1.025 which is totally acceptable..
I assumed approx 40gallons of actual water in your tank.
https://www.hamzasreef.com/Contents/Calculators/ResultingSalinity.php
Or for about $1 you could put a gallon jug with a drip line and a plastic air line valve... A variation of this has worked fine on all of my tanks for over 20 years, including a 700g system that can lose ~5g a day
I use a pitcher of rodi water on top of my sump, adjust my drip line to a medium drip, and refill the container every night. My water stays topped off for $4. I have a 120 with sump and refugium.
Sent from my iPad using Tapatalk
What's expensive ? You're adding RO water
mcgyvr
New member
"expensive" is relative..
If you are buying RO from your local fish store then 60+ gallons a month isn't exactly "cheap"...
mcgyvr
New member
The amount of evaporation depends on a few factors.. Localized humidity, exposed surface area, turbulence,etc...
In the dry winter months on my 80g tank with 4ft x 2ft of surface area I'm evaporating about 2.5G a day...
Keeps my house nice and comfortably humid though at about 50-55% humidity so I don't need to run a dehumidifier..
On a 46g I'd expect at least a gallon a day in the drier months..
Now slap a cover on it and you can drop that quite a bit but you also run into potential gas exchange issues..
I'm actually going to create an acrylic top for most of my tanks surface but I have an uncovered sump and am not concerned with gas exchange in doing so.. It won't be a total/sealed top but my hope is to cut down on some of the evaporation too just to decrease the work/time/amount of RO water I need for top offs..
If you're buying 60+ gallons a month, you should be buying your own RODI filter
mcgyvr
New member
yes.. that is certainly true..
but again I'm not in their shoes and even running your own there is still cost involved in it.. Its not free and is usually a few bucks a month just for filter costs....
again.. expense is relative but the amount of evaporation can be slightly problematic for some..
Thanks. My 46 is covered, probably about 80% or so. I think it's less than a gallon a day but does seem to be loosing more than when I hat it set up 5 years ago. I've just been using purified walmart water. Start up costs and space put limits on getting my own unit. (plus for a 46 it seemed like a bit much)
