Converting marine to fresh water?

[anne-marie]

I currently have a marine aquarium which doesn't have any animals in it. I need to change it to a freshwater tank because my axolotl collection is growing! Can i use the same filter media (carbon internal filter)? The substrate is coral sand but I don't think I can use this in a freshwater tank. Can anyone help me with this?

 

[peter]

hi Anne-Marie.

not entirely sure but from what i have just read on the web, i would guess that the filter media already present would be suitable. the established bacteria would probably be the same as those in freshwater filters.
my concern would be the coral sand. do you mean it's 'crushed coral'?
crushed coral can be used to elevate pH levels and maintain the pH at that higher level. crushed coral contains calcium carbonate (which raises the pH).
might be worth checking out the pH level as it is without beasts in it.

peter

 

[brian]

Yes, you can easily convert your saltwater tank to fresh. Here's how:

Filter - no change here. You will have to do frequent water changes for the first week to flush the system though. With no animals in the tank, change all the water to fresh, and do a half water change every day for a week. This will flush the salt and decay from the system.

Substrate - this will need to be completely changed, as coral sand would not be good for axies. However, it can be used with some kinds of fish, most notably african cichlids.

Tank and Decorations - these just need a thorough rinse with warm water to get rid of any salt residue. Same goes for any other gear you might be using (filter intakes, spray bars, etc.)

Certain other gear from your saltwater tank will not be used at all. Skimmers, heaters, refugiums, calcium reactors, UV sterilizers, etc. are completely unnecessary. You may need a chiller depending on your local temperature. I see you are in Australia, and a lot of people there are having problems keeping the temp down in the summer.

 

[anne-marie]

Okay, cool. I didn't think the coral substrate would be suitable, but I'm glad I don't need to buy a new filter. Thanks guys!

Brian, we are heading into winter here now so heat shouldn't be a problem and as for summer I have no idea how people survive over here without air-conditioning. My 7 year old axolotls have weathered the temps so I guess Gleek and the Wonder Twins will too, eventually.

 

[brian]

Glad you're not having temp problems. Just remember to do water quality tests before you add your animals, just to make sure that everything is ok. You'd be amazed at how many marine animals are living in your filter that will die off and foul the water when you switch it to fresh.

 

[anne-marie]

Ok, I've changed the water and substrate. Is there any particular part of the water quality I should be testing for or do I need to do the whole gamut of pH, ammonia, nitrates?