Upgrading But How Do I Swap Over?

[Villy Valley]

As you know I have been keeping my goldfish in a 29ltr tank and as pointed out to me this is far too small. Tonight I am taking the plunge and hopefully will be buying a second hand tank which is 3ftx2ft - so this is a lot bigger than the one I have!! I do not have bags of room and the new tank will be position where the smaller old one is situated. Can some one tell me how to swap over. From looking at previous postings I can see that I need to give the fish the water that they are in already. I need to put the filter that I am currently using into the new tank so that the friendly bacteria can get into the new tank. I need to put the sand bed from the existing tank into the new one along with enough sand to cover the bottom with about 1inch. I plan on doing my usual 20% water change where i hoover up all the crap off the bottom and then top up the existing tank. I then plan to syphon off enough water to from it to house the fish in a small - yes small fish bowl. I will then fish out the fish and put them in. I then plan to syphon off the remainder of the water into a clear plastic tub. At this point I will have to switch the two tanks over. I will then put the sand from the old tank into the new one plus adding additional sand. Then I will put the syphoned water from the tub into the new tank and then fill up with tap water that has been treated. I will set up the old pump in tandum with the new one so that the friendly bacteria can get into the new tank. I will also add the ornaments from the old tank into the new without cleaning them. Can I put the fish straight back in or what should I do next. The goldfish bowl is only holds about 3 litres of water and so it is literally a holding tank. the fish are 1 black moor 2 other fancy goldfish, 2 cloud mountain minnows and a hillstream louch. I know they cannot stay in fish bowl so my dilemma is will they cope with going in the new tank - if it is not cycled.

Villy Valley

 

[Villy Valley]

Looking at the tank tonight! Advice please

Villy Valley

 

[madmom]

With your old filter running in tandem and the old tank water and sand in there you should be fine. I switched up from a 10 to a 20 gal that way and had no problems. you already have the bacteria in the sand and old filter. Leave the old filter in your tank a couple of weeks to play it safe while your new filter develops it's bacteria. Don't get new fish for a while though.

 

[Tolak]

Sounds like you have a pretty good handle on it. My only concern would be the sand clouding the water for a bit. The tank, water, & decorations don't hold your nitrifying bacteria, your filter does. The tank is just a glass box.

If you switch everything over, you have just changed the box, nothing else. I upgraded three 20's to 29's a while back, along with a fourth 20 to a 30. These were and are bare tanks. I put the fish in buckets with sponge filters & a heater, as it took a few hours. I put the filter media in a seperate bucket. The new tanks also went in the same rack space as the old ones, so I had to re-level a couple of racks. It was a fun, wet afternoon, a few hundred angels, plus a few corys & bristlenose.

Your water holds little nitrifying bacteria, these tanks got 100% fresh water. If you make sure the tank water is the same temperature as the bucket, there is no acclimation process. As it was already stated, run your old filter on the new tank, along with the new one. Overfiltration is a good thing, this will also give you a spare, smaller filter to use if you ever need to set up a quar or hospital tank.