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salt water to fresh water conversion questions.

2K views 7 replies 4 participants last post by  JimBinSC 
#1 ·
I have a 75 gallon sw that I want to transfer my 29 fw into.
I plan on draining the sw tank, placing sand and rock in a tub with sw and some flow.
I will remove any snails or other critters into another container. There's no fish in it.
After cleaning the tank I want to fill it with water and use the water from the fw tank and the sand, the filter,etc. Then add the fish.
The cycle should bee minimal if I do that right? There should bee no issues with just dropping the same fish in, right? Can I use the marine sand as a partial substrate if I don't have enough sand to cover the bigger tank?

One more question. I have a single clown loach that is about 5 inches long. Can I add smaller ones without the big one harassing them to death? Should I out the small ones in first then add the big one later?
Thanks
 
#2 ·
Nothing that has been in a SW tank should be added to a FW. As for the sand, I would assume the SW sand is calcareous, and unless you have hard water fish like rift lake cichlids, this type of sand should not be in FW at all.

Are there plants in the FW? The sand will be insufficient for a 75g if depth for plants is needed, so I would get some inert sand. I use play sand, but you may want to match whatever you have.

The transfer of nitrifying bacteria would occur with the filter, any wood/rock/decor, and the present sand in the 29g, provided none of this is washed under the tap.

You want to ensure every trace of salt is removed from the tank, and having never done this, I can't offer any suggestions, but others probably will have some.

As for the loach question, that should not be a problem. The existing loach might be rather territorial to any newcomers, so keep an eye on it.

Byron.
 
#4 ·
Indeed it will. Why have you decided to switch from SW to FW btw? Just curious. And very curious to see how this develops as you have a lovely sized tank to work with!

Just make sure you get it clean though! Neither your fish or plants will thank you for the salt! If it was me I'd have it outside with a scrubber and a hosepipe on it for days! Espec in amongst the seals etc!
 
#5 ·
Several rinses with tepid water should rid the tank of the salt. As Nilet699 said, pay special attention to any nooks and crannies. I wouldn't worry about using any water from the 29. That won't have any real impact on the cycle. The items mentioned by Byron are the most important. The live plants will provide a great safety net and make your tank morhealthy and natural looking in the long run. Good luck !
 
#6 ·
Thanks to all who responded with answers. I never would have thought to scrub the seals other than a quick wipe down.
Nilet, as Byron may or may not remember I have been tossing the idea around of which tank to be fresh and which to be salt for awhile. I planned on making the 75 fresh but changed at the last minute. Looking at the cost comparison of outfitting a proper 75 or 29 SW with overflow, sump, proper lighting, etc the smaller is cheaper but I give up variety. Also I have a clown loach that is outgrowing the 29 (as expected) so a tank upsize or fish trade is needed. I am still considering my options.
 
#7 ·
Thanks to all who responded with answers. I never would have thought to scrub the seals other than a quick wipe down.
Nilet, as Byron may or may not remember I have been tossing the idea around of which tank to be fresh and which to be salt for awhile. I planned on making the 75 fresh but changed at the last minute. Looking at the cost comparison of outfitting a proper 75 or 29 SW with overflow, sump, proper lighting, etc the smaller is cheaper but I give up variety. Also I have a clown loach that is outgrowing the 29 (as expected) so a tank upsize or fish trade is needed. I am still considering my options.
On the clown loach, remember that mature fish need a 6-foot tank at minimum, and this species needs a group because of its high social interaction, so 5 or more. I mention this here because if the larger tank is not an absolute, rather than adding more loaches that will not be in suitable surroundings shortly, it would be better to re-home the existing loach.

This has always been my approach, when I have mistakenly acquired potentially large fish--something that in the distant past was possible, though obviously not now. My adage which I have followed for the past few years is that I will never buy a fish that I do not know all about, nor will I buy any fish for which I do not now have the appropriate tank running. This has saved me considerable grief I'm sure, not to mention the fish.:)

Byron.
 
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