Evaporation of water...

I had a quick question. I have a 17 gallon reef tank, 20pds of live rock, 20pds of sand. To be honest it only takes 14 gallons of water because of the rock and sand. Anyways, my water evaporates quickly, Im assuming from my T5 lights. The water will drop about 3 inches a week. I add RO water every 2-3 days to keep my salt perimeters perfect and I also like to see my tank full. Since I do add like 3 gallons of RO water a week, is this considered a water change???

I also fan my rocks and sand every week to pick up any little things, which I see my filter take in pretty well.

Added some pics of my tank, a torch, and duncan which I added today.


I also like to thank everybody for there opinions on my dying coral, Thanks...

 

No, replacing evaporation is not considered a water change as nutrients do not evaporate and still need to be exported out of the system.

 

As above, also your water change has the added benifits of replacing the elements which your live stock consume to grow (dosing these things is another topic)

 

Exactly what bill said, but staying on top of that evaporation is almost as crucial as doing water changes. Salinity swings can be detrimental to most aquarium fish, coral, inverts, damn near anything. But you seem to be on top of it so no worries. just do you water changes n you should be good!

 

It is not a water change. When the water evaporates, all the ammonia, nitrates, nitrites, phosphates, etc not only are still there, but they are actually in a higher concentration as your water volume has decreased. Try to top off your tank daily, to keep fluctuations to a minimum, I do. Also, IMO, you should do a 10% water change weekly.

 

Great tank! May I ask what your feeding your Feather Duster? Very pretty