Water Evaporation??

How much should be evaporating each day? We have a 75 gallon tank with a 20 gallon sump/fuge and its needing water to be added at least once a day. Its getting to be kind of annoying to add water so often, I didnt have to add so much in the smaller tank (36 gallon) which seems strange to me. Any suggestions on how to make adding water easier or evaporation happen less often? Thanks!

 

Get an automatic top off system. I top off about 1 to 1.5 gallons a day on my 75 with a 40 gallon breeder sump and 26 gallon refuge.

I wouldn't worry about lessening evaporation.

 

I will look into getting one, anyone have any luck with the DIY automatic top off systems?

 

They use sensors hooked to a pump that turn the pump on when the water level is low and off when it reaches the height you want your sump. You have a container of water that the pump draws from. Check Melev's reef for a good description on a DIY one.

 

I have the eshopps automatic float vlave that I have had running for almsot more then 9 months...It's an amazing peice of equipment with out the hassle you having to use an electronic pump and installing switches here and thier...
must say It's sure worth 35.00 through our LFS...

 

I have about 75g including my sump andI have to fill about 2.5 gallons every 2 or 3 days. my lights put off crazy heat though

 

1% water volume per day is typical. It can depend quite a bit on your location and local humidity though. I definitely think an ATO is a good idea, but stick with good ones, as a malfunction can kill everything in your tank (I.e. not JBJ ). Reef Fanatic, spectra-pure, litermeter, Tunze or if you are a diy'er, autotopoff.com. Whatever you do though, make sure there is a redundant, high level shutoff in case the first sensor malfunctions (someday it will).

 

+1 on the ATO...ive been meaning to build one because i top off between 2-3 gallons a day, just been lazy and sick lately lol

 

The 75g tank has larger surface area contacting the air than the 36g, thus the difference in evaporation. Several factors contribute to the evaporation like heat from your lights or the air movement over the water's surface ( Does your tank sit in the path of a ac vent?)

The amount you are losing is normal and you shouldn't be concerned. I don't mind topping mine off ( I top off at the wet/dry) because It gives me a chance to give my system a once over. ATOs are popular for large aquariums or I know several people who hook up their RODI unit to their sump with a float valve to act as a ATO.

You could also look into a lid for the tank to reduce evaporation

 

I was thinking about putting a 5 gallon bucket that will gravity feed into my refuge with a float valve in the return section. It's just an idea so far, but I've been having the same mindset as you, kinda tired of filling the lower section with the little cup i use. Does anybody use a top off similar to this?