Cycling question...
 

Can I use a seeded sponge filter from a freshwater tank for a saltwater QT tank??

My main tank is heading into its 3rd week of set up and want to make sure I have a QT tank ready too.

Thanks

There are some pretty mixed opinions about this over the years.

What I think is this: if you put your freshwater fish into a saltwater tank, do they live? Then, I am thinking their buddies don't either. JMHO.

I have to agree with EmilyB. But also with that cycle stuff that you can buy that is suppose to speed up the cycle it says it can be used in fresh or salt so who knows. But who knows if that cycle stuff actully works anyways. I also here you can pee in a tank to get the cycle started, but again another mystery.

Re: Cycling question...
 

As far as I know... it cannot be done. Most freshwater organisms will literally shrivel up if you stick them into saltwater. In the opposite situation, most SW rganisms will either swell or burst if placed in a FW situation for an extended period of time. This gets worse if you get into relatively simple organisms. For example. freshwater fish constantly try remove water from their bodies and saltwater fish are constantly "drinking" water. You can imagine what will happen if they're placed in opposite situations (assuming they survive long enough in the first place). Of course, bacteria continue to defy the "laws" of nature and new things are always being discovered... but as far as I know the bacteria that we use in our aquariums do indeed follow this general rule of thumb.

-Richer

Marnie, with the amount of live rock you have, this question is moot. There isn't anywhere near the amount of bacteria on a sponge as there is on all that rock you added.
But for theory's sake, I don't believe the bacteria are transferable.

:neutral:

For all we know some of the bacteria we're talking about can also exist out of water. Or how about anaerobic bacteria...

I didn't think it was a good idea, so Brad are you saying I should just take a piece of LR out and put it in my QT tank and that should suffice (w/ water changes of course)??

Thanks to all who responded.

Marnie, unless you need to treat the QT with meds, a couple of pieces of rock would be perfect. It also provides a more natural environment for the new fish.

I keep the sponge filter (and a spare) for my QT in the sump of my reef tank to keep it ready for the next newcomer. When I set up my QT tank, I use water from the reef tank to fill it, then replace the water in it with new. I do need to plan ahead so I can have a batch mixed, usually for a full water change while I'm at it. This system works well since there is no cycling of the QT required, and it helps to stall impulse purchases when there is no premixed water for refilling the reef. I don't bother with rock in my QT, I just go with some PVC pipes.