do you add salt every time you do a water change ?

[kaybee]

how much water changes do most people do ? their seems to be a very large range from what I have read on the net. is their anyway to reduce the required water changes ?

There's a very large range because each tank is a unique environment with unique requirements.

If the primary purpose of the water change is to reduce nitrates, employ some alternative nitrate reducing measures (add a refugium, increase the sand bed depth, add more live rock, etc). A FO/FOWLR tank with nitrates consistently at 5ppm or less would logically require fewer water changes than a system with nitrates consistently at 10ppm or more.

In a reef tank, though, water changes replenish essential elements which have been depleted or reduced, regardless of nitrate levels. I do huge water changes (50% every several weeks) on my reef tank even though nitrates are undetectable at all times.

20% to 30%? I was told 10% a week. Is that not enough for my 40 gallon?

Depends on your set up and the effects of the 10% weekly since each set up is a unique environment. If that interval and percentage changed out works for you, stick with it. Alternatively, increase the percentage and/or interval for 3 months and see if there is any improvements occur (which may or may not be evident). Make adjustments based on the results.

Salt water replaces salt water during water changes. I occasionally top off with salt water to replace salt removed from the system via protein skimmer skimmate (were I to continuously top off with RO/DI water, salinity would gradually take a dip).

[labnjab]

I always do 10% weekly water changes and top off with only fresh RO water. I haven't really had to top off with saltwater, I've never seen a drop in salinity due to skimming, but maybe that's because I do a really dry skim.

[cocoa_pleco]

Yellow tang

IMO those guys should have a 72" long tank, they need their swimming space

[melbfish20]

after doing a fair bit of research last night I have decided that it would not be right to keep a yellow tang in a 85 G.Some say it would be ok but I think that 100 G is absolute minimun , 125 G is more ideal.

[unleashed]

don't forget that it is not only the water volume which determines which fish you can and can't keep, it is also the swimming space.

IMO, an 85g would suffice for a yellow tang, IF you have lots of swimming space between live rock and open swimming space. Also, length of the tank also plays a significant role in determining suitable species

[jimpierce]

I figure I still have a few more months with out Blue Hippo Tang before he will be in need of more space. Now if I can convince my wife that we shouldn't get fish that will out grow our tank I will be so happy!