water evaporation ?

[rob1984]

not sure what size tanks folks running where water changes take place every 3 weeks or so. I do 90% percent water changes every week, evaporation is about 2 inches. on the 180, open top, and around 1" on the 140. 80% covered. no sumps.

ya usually once a week WC of 80-90% as well here but lately been a bit longer between changes due to higher turnover rate now. but gonna get the sump covered up and hope It helps

 

[the_deeb]

Relative water temperature and exposed surface area are the main factors - in my open topped riparium setup with a sump I probably lose 3-4g a week to evaporation.