Hey Guys, about to purchase a new tank for oscar and friends, its 6 foot, 140G(uk) tank, i think he is going to be impressed!!

just a few questions about moving everything, if we move them (for a few hours) into a smaller established tank (normally for our babies) and then move the 60G (or so) of water from their current tank into the new tank, moving the current filter and all accessories (plus the ones that are coming with the tank) topping up the water level using treated tap water and the operating the tank for an hour or so would it then be ok to add them straight in??

hopefully getting it over the weekend! cant wait!!

Yes

But you have to be very careful not to lose any of your bacteria.

I did exactly this when I moved mine a few weeks ago. Make sure the filter is switched off for the shortest possible time to avoid any loss of bacteria.

Will you be moving any your old gravel or sand. Its a messy job but that is where most of the bacteria live that don't make it to your filter. If not then you might find you end up in a mini cycle.

Good luck and contrats on the new tank.

This is what I did when switching and it seemed to work fine:

--move the oscar to the small tank

--turn everything off but the filters

--siphon old water into the new tank but leave just enough to keep filters going (since you have gravel I wouldnt think leaving them running while removing substrate would cause any clogging problem like maybe with sand)

--move substrate/decor/heater

--move filters

--siphon rest of the water, turning filters on as soon as theres just enough water (you should only need less that 2 or 3 minutes tops to get them running again)

--top off with treated tapwater

--turn the heater back on ( I always wait until the tank is full/nearly full before turning the heater back on b/c Im convinced the heater poses the biggest shock risk and Ive broken my fair share of heaters by forgetting to turn them off when draining the tank)

If you move them to the smaller tank the day before you will be ok. Move the filter with the fish. When you set up the big tank move the filter with them. Have the filter switched off for the minimum time and keep the media wet all the time

Thanks for th info guys, i was too busy getting th tank into my house and fixing it up ready for filling but its good to know i can avoid cycling the tank all over again.

filling is going to take place next weekend and i can see it will be a huge job as the tank is much bigger than expected (i have called in reinforcements who are on standby)!!

yes, i will be moving everything from the current tank into the new one including the gravel so hopefully alot of good bacteria should follow!! so should i avoid vacuuming the gravel for this week??

cant wait, oscar will look very small in this monster but i can just imagine how happy he will be!!

What I have done in the past is put my fish in a 5 gallon bucket. This is of course extremely temporary. Since you have a spare tank to put them in, I think they should be good for 24 hours. What I have done is put the new tank where you want it. Approximate how much "fresh" water is going to be going into the tank minus a couple gallons for substrate. Fill with fresh water and treat. Then start draining water from the old tank into the new tank. When you get to that point where the filter is beginning to not work properly, transfer immediately to the new tank. That way it's only shut off for 10-15 minutes. Hook it up to the new tank and start it immediately. Then finish transferring water from the old tank to the new. The hardest part I've come across is moving substrate. Usually I will transfer a lil at a time with a plastic kool aid pitcher. That way I can drop it right into the water and pour it out pretty much wherever I want it. After everything is moved, I let the tank run for an hour or 2 and put the entire bucket with fish into the tank and pour them back in. The whole thing is not a small job. It will be worth it in the end though. I guess the most important thing I can say is to make sure you don't turn the filters off for any longer than absolutely necessary and treat any fresh water going into the tank. Seeing how you have a spare tank, I would definitely consider moving the filters with the fish. That way they're always running. Good luck.

Its ok to clean the gravel, most of the bacteria live in the filter (unless you have an undergravel filter)