Moving To A Bigger Tank

It sounds as though you want to move everything across and just have the 180, not run both tanks?

The process is quite easy, but with a newly cycled filter you'll have to be a bit more vigilant. The filter bacteria live in biofilm and this takes a few months to fully develop. Until then, the bacteria colonies are more delicate. You will need to be careful during the transfer and monitor your water more closely afterwards compared to when I upgraded a 10 year old tank.

You have two options regarding the filter. Either take the media out of the old filter and put it into the new one, or run both filters together for at least 6 weeks. The first is preferable as with the latter the bacteria will spread out between the two filters in proportion to the amount of media; then when you remove the old one, you'll lose some bacteria. If the 180 has the same type of filter as my Rio 125 had, replace the carbon sponge with the old media and if there is still some old left, replace another sponge (green if they still use it). Don't remove the blue sponges or the cirax if that's included.

If the 180 is going in a different place you can take your time. Set up the new tank (check for leaks somewhere else first if that sort of thing worries you). Fill it with dechlorinated water and let it run to make sure the heater and filter work properly. Don't put anything in the tank just yet.
On transfer day, turn off the old tank, remove a bucketful of water and put the fish in it. Cover the bucket (a towel will do) as stressed fish can and do jump. If the filter will fit, put it in the bucket too. And the mossballs and bogwood/java fern, though you might need a second bucket for those.
Remove some water from the 180, slightly less than the amount in the 64 litre and replace it with as much water as you can get out of the 64l without distubing any muck in the gravel. Take out the gravel, wash it, put it in the 180 and add more to get the amount you want. Now move the filter, or put the old media in the new filter. It is fine to cut sponges up to make them fit, but keep everything wet. Put your decor in the new tank and if you use second bucket for the plants put the water in the 180 as well.
Strictly speaking, you should acclimate your fish as if you'd just bought them. But you have been doing lots of water changes with the fish-in cycle so your water won't be very different from your tap water. And about a third of the new tank's water is from the old tank so it's like doing a 65% water change. The main danger will be if the bucket has cooled down so the tank is a lot warmer. Maybe put the old heater in the bucket and switch it on to prevent this. Net the fish out of the bucket and add the water to the 180.


If the 180 is going in the same place as the 64l, it's a bit more complicated. You'll find a brand new dustbin will hold  the water from the 64 litre (more expense I'm afraid!). Empty as much clean water as you can into a bin. Half way through, transfer the fish, plants, heater and filter. Move the bin out of the way and plug in the heater and filter. Then empty the 64 litre, move it and put the new tank in position. Fill it up, switch the filter and heater on and wait till the water is warm. If you fill with warm water it shouldn't take long. While it is warming, you can be sorting out the gravel and adding any non-plant decor. Then turn the electrics off, remove some water and continue the transfer as above. Transfer the fish when you can catch them easily.


Wait at least a month before getting more fish. This will make sure the new tank has settled and the filter has recovered.


Using warm water to fill the new tank -
If you have a combi boiler, it is safe to use the hot water tap. But if your water is stored in a hot water cylinder, you'll need to boil a kettle. This type of hot water system fills the cylinder from a cold tank in the attic, and all sorts of nasty things can find their way into that; things you don't want in your tank.

The old filter media should be wherever the fish are.


The sponge is fine, cut it up if necessary to make it fit. The thing on the frame is likely to be a carbon cartridge, they usually are. It will have some of your newly grown bacteria. What you could do with that is to get or make some sort of mesh bag. I generally use a piece of net fabric (the kind little girls' dance costumes are made from) with a bit of thread run round the edge to gather it up tight. If you then cut the cartridge off the frame and onto the net you won't lose any bits.
To give you some idea, when I got my Rio, I used the media from the old filter. This was a long thin rectangular sponge and ceramic noodles. I cut the sponge up and put the noodles into a bag as I've described. Then a month later, I removed the built in filter because it was so noisy, and persuaded the old media and the new Juwel media to fit into an Eheim aquaball which uses cylindrical sponges. It was a bit fiddly, but it all went in.

With the Juwel filter, the water flows from top to bottom. Put the old media on top, then cover it with a white pad which is designed solely to catch bits in the water. The water will wash any loose biofilm and bacteria deeper into the Juwel sponges.
It's just occurred to me that you said the tank was second hand. Did you get any media with it or will you need to buy new?


If you intend planting the 180, ignore what I said about moving the gravel over. Use new and get the plants growing well before you move the fish. Well growing plants will help to remove any ammonia spikes you might have. It sounds like you won't be able to put the old filter in a bucket so remove the media and put that in while you remove the water from the 64 litre. You need to keep it wet. You won't be able to use the last inch or so of old water as that'll get full of muck from the gravel. You'll be surprised just how much there is. I know from experience 




Edit: nearly forgot. Let the new tank run with fish for a couple of months then remove the old media a bit at a time every few weeks till it's all gone.
Juwel filters use a white pad on the top. These get dirty very quickly and will only wash a couple of times before going into holes. Replacing them every couple of weeks means there won't be time for many bacteria to grow in them so that's not a problem. But they do work out expensive. Buy a roll of filter wool (pond departments are your best bet) and cut that to shape. It's much cheaper.

That seems very odd. I remove artificial plants all the time. I take big ones out during a water change as they get in the way; I swap them between tanks if I think they'd look better in the other one.

There is one possibilty that occurs to me, thouhg you do say you didn't disturb anything. Do you have the base of the plants under the gravel? Mine just sit on top, but they would look better with the bases buried. I have heard of cases where fish have died after gravel disturbance. It is thought to be a build up of waste in the gravel, especially if the plant bases have been in the gravel so you couldn't clean thoroughly next to them. The buried waste decomposes and can become nasty.

If it's not that, I'm at a loss to know what happened.

Some fish are more susceptible to infections than others.  It is possible the cardinals just coudn't cope. Keep an eye on the rams are they are notoriously sensitive fish.

White spot is very common but it is easily treatable. Follow the medication instructions to the letter. The bug has a three stage life cycle (on the fish as the spot, on the tank bottom as a sort of cycst where it multiplies, and free swimming looking for a fish to infect). In the first two stages it has a coating so the med can't get to it. The third stage is the only one where it can be killed and there must be some active med in the tank when every last one gets to the third stage. Just because the spots vanish from the fish doesn't mean to stop treating - stopping too early is the most common cause of a repeat infection.

In theory they should be OK to move next weekend. But don't disturb the bottom of the tank when you remove everything and don't use the last couple of inches of water. And if there are still any spots on the fish, I'd wait a bit longer to move them.

Thanks Jesnon, I lost the Rams sadly but all of the Dwarf Rainbows and both Otto's seem to be quite lively today (had second dose of treatment)

I'm a little wary of putting the filter media from the infected tank into the new one when I move. Do you or Sue (or anyone else) know if it should still be ok or should I cycle the new tank before moving the fish?

Also, should I still use the water from the old tank to help acclimate the fish?