Evaporation

I just installed a 70w metal halide lamp a few days ago when I added frags to the tank and my water seems to be disappearing quite quickly causing my specific gravity to rise slightly to 1.025 from 1.024. I have been adding in fresh water to bring it back down but it seems like it is going to be a daily chore any ideas on how to stop that ?

 

Your going to need an ATO if you don't want to top off manually.

 

Yup no way around evaporation, you can decrease the evaporation rate with a lid. Personally I would rather top off or as suggested get a ATO.

If your keeping corals you probably want to keep your SG around 1.025-27.

 

MH = warmer tank = more evaporation. You can run your lights less, run them when it's cooler (at night), etc. You could get a chiller that will keep the water temp down (if you use fans, your evap will increase), which might help, as would keeping your room-ambient temp down.

You can also get an Auto Top Off (ATO) that automatically tops your tank up, so you don't have to do it yourself, altho you do need to keep the reservoir filled. These can be DIY'd or bought as "finished" ATO's. I've always been partial to the Tsunami ATO myself, but I also do plenty of manual top ups on our non-ATO setups.

Wow...2 peeps replied while I was replying...guess that'll teach me a walk away mid-reply! LOL

 

I also have a damsel and a pair of ocellaris, would the higher grav. be okay for them as well? Also, should I be needing to top off daily?, it seems like a bit too often to me!

 

Yeah the fish will be fine.

You need a refractometer and you need to figure out what the evaporation rate is and either go the ATO route or top off daily. You want a consistent value, as little swing as possible and that usually mean an ATO or daily top off.

 

Well I will just have to do it manually I just looked up the ATOs and they are too expensive for me, in fact the cheapest one I saw cost as much as my tank lol!

 

Others will put my numbers to shame but my tank evaporates about 7 gallons a week. You really should figure a way to auto top off for times like when you go out of town.

 

auto top off arent that expensive... you can get a decent one for like 80 bucks plus a small pump, float valve, and 5g res and you're set shouldnt be more than like 120 for a decent set-up

 

We generally like to run 1.023, but we're more about the fishes. That being said, I'd run it a bit on the "lower" side, like 1.023 if you have lots of evaporation, simply because if something happens and for some reason, you CAN'T top off, your SG won't go too high. Personally, I get concerned if I see 1.025 in our own setups. However, once you get your evaporation under control, it's OK to run your SG a bit higher if you so desire.

HTH