Why Transfer Old Water???

[Marco S]

I have seen several posts where people recommend transferring old tank water to a new tank when upgrading tanks. From everything I have read or watched, bacteria live on surfaces such as rock, sand, filter media etc... not in the water column itself. So, why would you want to transfer your old water to a new tank? Wouldn't you just want to make sure the salinity, PH and Temp matches and use all new water?

Sorry if this is a dumb question and the answer is obvious, but it really bothers me when I don't understand something.

 

[reefpunk707]

I believe its to kick start a cycle or to add beneficial bacteria from an already established system

 

[Scurvy]

Mostly so you dont shock any tank ihabitants with to drastic of a change. Yes you can match salinity, temp and PH but what if youre NO3 and PO4 are 25 and .2 then drop to zero? Corals would be quite angry.

 

[Marco S]

I believe its to kick start a cycle or to add beneficial bacteria from an already established system

But there is no beneficial bacteria in the water itself...

 

[Marco S]

Mostly so you dont shock any tank ihabitants with to drastic of a change. Yes you can match salinity, temp and PH but what if youre NO3 and PO4 are 25 and .2 then drop to zero? Corals would be quite angry.

That makes sense...Thanks!

 

[cracker]

There is some bacteria. Also the old water is what the critters are used to . I don't know certain elements ,temp, salinity ect . So use what old water ya can then the rest with new .Next round use all new . I'd think it would be easier & less $$ to use old water once .

 

[Marco S]

There is some bacteria. Also the old water is what the critters are used to . I don't know certain elements ,temp, salinity ect . So use what old water ya can then the rest with new .Next round use all new . I'd think it would be easier & less $$ to use old water once .

Didn't think about the money. You are right there, I would have saved a bit of money in salt and even the extra use of the RODI filters to fill up my 200 gallons if I would have had water I could have transferred from another tank.

 

[MnFish1]

I have seen several posts where people recommend transferring old tank water to a new tank when upgrading tanks. From everything I have read or watched, bacteria live on surfaces such as rock, sand, filter media etc... not in the water column itself. So, why would you want to transfer your old water to a new tank? Wouldn't you just want to make sure the salinity, PH and Temp matches and use all new water?

Sorry if this is a dumb question and the answer is obvious, but it really bothers me when I don't understand something.

You're right - I do it because the fish coral etc are used to the 'water they're in' - and it doesnt make sense to shock them with new 'chemicals' or take away other things they are used to completely. Theres no such thing as a dumb question. (PS - I dont think it jumpstarts the cycle). There shouldn't be a 'cycle'. Especially if you're using some of the same filtration, etc and not adding a lot of 'new' rock, etc.