Acute evaporation = partial water changes?

[fishb0ne]

I'm on a roll today with the questions
75g palludarium, half sand, half filled with water to about 6 inches, meaning roughly 10 gallons. This palludarium houses a colony of 8 crabs. I've got some acute evaporation issues and there's not a thing I can do about it.
The ambient temperature in the room is about 67-70*F. The palludarium is heated using a 40w ceramic lamp to a comfortable 73*F. The water is kept at 77*F. I have to compensate almost a full gallon every 2-3 days. So in about a week I add roughly 3 gallons. It also happens that my weekly partial water changes are exactly 3 gallons.
Since I've got so much evaporation, can I stretch my partial water changes to once every other week?

 

[Lonewolfblue]

Stretching the water changes probably wouldn't be a good idea. Evap is not a water change, the only thing that evaporates is the water. Eventually you will get a buildup of minerals, etc, and the water parameters will fluctuate more. You will also get a buildup of nitrates as well, unless you have enough plants to use them up.

 

[hashbaz]

Like LWB said, the point of a water change is not to remove water, but to remove the gunk that is in the water. Evaporation leaves all the gunk behind.

You may be able to stretch out your water changes - for reasons like live plants, heavy filtration, low bioload - but not because of lots of evaporation.

 

[DanD]

Agree with all of the above - fact is, the more evaporation you have, the more build-up of dissolved solids you'll get. You could make a case that, with more evaporation, you'll need more/larger partial water changes, not less.

 

[Lonewolfblue]

Agree with all of the above - fact is, the more evaporation you have, the more build-up of dissolved solids you'll get. You could make a case that, with more evaporation, you'll need more/larger partial water changes, not less.

That is another good point.....