Quarantine tank

Ok so i've heard people say that you should use water from your main tank for your q tank. My question is does it ALL have to come from the main tank? I only have a 28 gallon main tank and a 10 gallon q tank...it just seems like removing a lot of water. Could i put maybe three gallons from the main tank and maybe a handful of sand from the sand bed?

I would assume that the purpose is to put good bacteria in the water so the tank is pretty much already cycled. If i'm completely missing the point, fill me in

 

The water doesn't have enough bacteria in it to be an issue. The inportant part is that all the params are as close as possible. Temp/PH/SG etc

 

I have a 55 gallon tank and a 10 quarantine, i never used tank water. Just mix it up as you would normally. IMO it as long as the parameters are somewhat close it will be fine. I acclimate fish to the quarant. tank then acclimate them again to the main tank, so it doesn't really matter. If you quarantine tank is not cycled, just make sure to do some water changes every couple of days and test for ammonia and nitrate, you should be fine unlesss you have some real sensitive fish

 

I always use all display tank water for Q-tank change or start up. When I go to put livestock in the tank I run weekly water changes on the Q-tank with display tank water so that the parameters are solid. I just add new water back to the main tank to make up for what I use.

 

You're completely missing the point. More accurately, you're missing a fact. Water doesn't contain bacteria. Water doesn't cycle. Tanks do. It's the surface area of the system that houses bacteria. By that I mean every available square inch of surface area is where beneficial bacteria grow. That goes for live rock, glass, sand, insides of pipes, even the power cords dangling down into the tank for the powerheads. This is where the bacteria grows. You can take water from a well established tank, or from an RO/DI system, it doesn't make any difference insofar as how livestock will fare in said water.

As Otty suggests in his post, though--the reason it's a good idea to take water from the main tank for the quarantine tank, is because the the paramaters will be identical, providing a less stressful transition for all inhabitants who move from QT to display, or the other way around.

So to answer your question, you don't HAVE to use water from your display tank to fill the QT, but that is the best way. Drain it from the DT, and use newly mixed SW to replace it.

If you didn't mind more work, you could simply use newly mixed SW for the QT, but you'd want to spend extra effort to make sure that all paramaters match the DT as closely as possible. I think when you consider matching salinity, alk, calcium, mg, etc., you'll find it simpler to just take from the DT.

Hope that helped.