Tank change, keep water or us all new?

[watson_barrett]

I am getting ready to switch my tank over. I have a 50G up and running now and i am putting up a 92G bow. My question is what percentage of my old tank water should I use?

A) All

B) None

C) bank gallons

D) Mix new water and old water gradually over the next few days so it is eventually all the same water?

E) Something else???

thanks.

 

[watson_barrett]

C) is use blank gallons...

 

[plyr58]

30%

 

[Ebmorri]

I say A and D. Move what ever is in your 50 over and then add new to that. You will keep your bactiria from the cycled tank and then add new sw to it to make up your 92gl tank. If you use all new water you will have to let it cycle all over again. If you you could try using less of the old water however you may remove too much and again have amini cycle.

Erick

 

[plyr58]

Bacteria must have a medium on which to reside. Therefore, there is very little, if any, nitrifying bacteria present in your water column. I say about 30% because your fish will always benefit from a good water change, but they can go it a bit of a shock going from one water quality to another.Unless you plan on drip acclimating them for an extended amount of time to the new tank water before moving them over, that is the way to go.

 

[watson_barrett]

Yea i was thinking use about a good 50%, which would only really be about 20 gallons at most due to the amount of rock in the tank...

 

[H2OLUVSME]

When I transfered livestock from one existing tank to another I mixed all the water from each tank together. I did this by swapping 2 gallon buckets of water from one to the other over the course of a day. Then, all I had to do was temp acclimate.

 

[Ritten]

I would try to keep at least 75%.

 

[sean48183]

Unless you have really high nitrates use as much as possibe. It will save money on salt.

 

[flyguy7150]

When i did my 46 to 90g upgrade, i used everything...well as much as i could so like 98%.

 

[Toddrtrex]

A couple of weekends ago I redid my 58. For all intense and purposes I did NOT reuse any of the water.

(( I started off by taking my sump offline and cleaning it out, before I did the main tank the sump was online again for a couple of hours, so there was some "old" water in the sump ))

Other then that, all the water was new --- I had a horrible bubble algae outbreak so I didn't want to risk any spores getting back into the tank. I put the water back into the tank in 5 gal bunches, was mixed for about an hour before hand.
Finished refilling the tank around 3 PM on a Sunday, put all the livestock back in around 6 PM on Monday. (( there were in rubbermaid bins with the old water and liverock )) Everybody is doing great and all the parms are in check.