Converting a salt tank to freshwater

[wilddiscuss]

Hi I have a marine tank right now...and I am changing it to fresh water. The question is.... can I just bring the salt water to fresh water and still use the bacteria? I am cycling my fresh water set up. But my marine is much smaller. I was going to use it as QT tank. I am going to get rid of the fish ofcourse to buyers. Then do some large water changes to bring the salt down to fresh. Is that safe or possible? I was just thinking about it. Because I was going to just cycle it like my other tank or get a sponge wich I think I'm gonna do for my show tank. Thanks for your time :)

Todd

[Ed13]

Sorry Todd, the easy way is not for discus keepers;)

This way will only get rid of the salt, but it won't do anything for the unseen, the flora and fauna among otyher things that slowly grows and cover the surfaces of saltwater tanks, which will start to decompose on your water releasing who knows what into the water.

What you need to do is get rid of everything fish, rock etc,. From here I personally like to bleach everything and disinfect what will be reused, scrape the glass to remove coralline algae, calcium build up, salt creep etc you may need to use vinegar or other acids(NOT AT THE SAME TIME WITH BLEACH). Basically try and make it as new as possible. Then asses the situation. What do you need new, replaced or adapted to make discus happy and also figure out what will this set up be. Then you can take it from there. Set it up, cycle etc.

HTH

[pcsb23]

I thibnk Ed is correct, in theory it should work, but in practice I doubt it will. I am assuming that its a plain marine tank, ie no live rock etc... Easiest and safest to break down, clean and start over imo.

[wilddiscuss]

Thanks all that does help. So first I will start with bleach and water...and clean the heck out of it. New bio balls and all. Thanks :)

[Apistomaster]

You can reuse the bioballs just bleach and rinse them.
Just don't use the old substrate because it is probably aragonite or crushed coral sand and it will cause your pH and hardness to be too high for discus.