Tank Upgrade

[MeanHoney]

I've just bought a 75 gallon tank and want to move the fish in my 20 L to the new tank. The filter on my 20 is a biowheel, so I can't move the media to my new filter (Eheim 2028). But will running the old filter along with the new filter help me avoid a cycle in the new tank? If so how long should I run both filters?

 

[Miss Wiggle]

yes run the two filters together on the old tank for 2 weeks, then set up the new tank, move the old filter and the fish across at the same time you'll need to keep an eye on your levels of ammonia and nitrite, as you may have a mini cycle in the new tank but it should be relativley quick and painless, just do regular small water changes for a couple of days to get on top of it. Basically the amount of bacteria needed to support all the fish you have will spread out between the two filters, so when you go back to just the 1 filter for the new tank you'll only have some of the bacteria needed. Hopefully it'll be enough to get you through without any cycle though.

 

[MeanHoney]

Thanks Miss Wiggle!! But, I can't really run the new filter on the old tank (its too big!). Will running them together on the NEW tank help?

 

[Miss Wiggle]

yeah that's fine, as you said it's a biowheel i thought it was a built into the hood type jobby that you couldn't move across. if you can move it then that's fine to run them on the new tank

 

[DevUK]

You might want to try and take some of the old water with you too to help out if you can...

 

[Miss Wiggle]

You might want to try and take some of the old water with you too to help out if you can...

not true, the nitrifying bacteria is sessile, meaning it does not live free swimming in the water but lives on things like ornaments, gravel and mostly in your filter media. transferring water just means at a stressful time for your fish (i.e. moving tanks) you're giving them partly used water with higher nitrates than with all new water.

transferring gravel etc can theoretically help you but the amount of bacteria kept in there is so small the effect is pretty minimal.

 

[MeanHoney]

Thanks for all of the advice. Is it worth transferring ANY of the water? Even if I was able to get 15 gallons from the old tank that would only be 20% of the capacity of the new tank. It seems like it'd hardly make a difference.

 

[Miss Wiggle]

nope, the reason you transfer anything is to keep as much of the nitrifying bacteria as possible, but the bacteria do not live free swimming in the water, they are attached to surfaces so moving the water will do diddly squat, best to start afresh with new

 

[vinylman]

Of course, if the water in the old tank is clean, you'd need to use less tapwater whilst filling the new one. It'd be nice mature water, too.

 

[Miss Wiggle]

Of course, if the water in the old tank is clean, you'd need to use less tapwater whilst filling the new one. It'd be nice mature water, too.

really sorry but it bothers me a lot when people use that term, there's no such thing as 'mature water' the bacteria does not live free swimming, fish tank water is just dirtyer than tap water that's all! it's the filter bacteria that keep it clean.

transfer over the water and it will have a higher nitrate content meaning you'll need to do a water change soon, use all new water your in effect doing a 100% water change and it means your starting afresh and don't need to do a water change quite so soon.

it's very stressful for fish moving from one tank to another, you want to give them the best possible start in the new tank. using old water does not do that.

[/rant]

 

[vinylman]

Depends when the last water change in the old tank was.