Switching out tanks

[chelli]

how much water do you suppose that i need to salvage from my 50 gal fw to put in my replacement 50 gal fw to prevent new tank syndrome. (the old tank is leaking and needed replacing today) I am assuming about 50% as that is what we did when i worked at the big pet store 2 years ago.. any opinions???

 

[TankGirl]

It is not so much the water that needs to be transferred as it is the substrate, decorations and (most importantly) the filter. If you moved all of those objects over without allowing them to dry out and put in almost completely new water you might avoid a cycle.

However, dredging up substrate and moving it means you run the risk of a cycle anyway due to the detritus taxing the bacterial colonies. You'll need to monitor the water carefully in the beginning. The benefit of moving the water is for the comfort of the fish, so the water in the new tank is as close to what they are used to as possible. Good luck!

 

[chelli]

well it went well.. i saved %50 of the water and lost no fish.. the water is clear and not cloudy and all is great.. I am so proud.. only took 3 hours with two people working non-stop. Even managed to save %100 of the substrate and the goo in it. Put a flat piece of plastic over the substrate while adding back the 25 gallons of cycled water.. it didn't even get real cloudy to start with.. cleaned the filter cartridges and by this morning the water was sparkling clean and crisp. And the fish are healthy happy and not dead.. the most important factor..thanks all