upgrading from a 60l biorb to a 125l rectangular shaped tank

im looking for advice the best way to move my fish to a new tank, i have 2 giant danios, 4 neons, 1 apple snail and 8 4 week old molly fry. i currently have a 60l biorb and will be looking to transfer them to a 125l fluval, thanks

Welcome to our aquarium club.

Before you move the fish, you need to make sure the new aquarium is properly cycled. This website has quite a few postings about the nitrogen cycle, but in basic terms it involves growing a colony of bacteria that turn aquarium wastes into plant food. Without the bacteria -- which live in gravel, filter media, decorations and plants -- the waste products will produce fish killing ammonia. You can buy an inexpensive test kit that measures ammonia. Be sure it stays at zero before adding fish.

To get the nitrogen cycle started, put some gravel, plants, filter media, decorations, etc., from an established aquarium into the new aquarium. A live floating plant like hornwort will also help the cycling process, which usually takes about a month. When the aquarium is ready for fish, use the drip acclimation technique to introduce them into the new tank. Check out the blog about drip acclimation.

I hope this answers your questions. If you have more, we're glad to hear from you.

thanks for that. will it help to use water from my biorb in the new tank, and also i have about 8 silver molly fry in my tank will they be ok to move once the new tank has cycled, thanks

Most of the good bacteria are in the gravel, plants, decorations, etc. Just putting in water from an established tank will not do much for the cycling process. One of my postings or blogs about the nitrogen cycle goes into more detail about an experiment I did setting up a new tank. A large bunch of hornwort and other live plants kept the ammonia at zero, or at least that's what my testing showed. Normally you get ammonia spikes starting a few days after the aquarium is set up. If you're going to have live plants you should still test for nitrites, nitrates and ammonia.

About the silver mollies: they're a popular aquarium fish, but mollies tend to get sick easily and spread things to other fish. Before mixing fish species, it's a good idea to find out which aquarium environment each species needs. Many species are compatible, but many are really not.

Be sure to keep us posted about your aquarium adventure.

Welcome to our forum!!!

It's so interesting that you ask about Mollies...

I was just reading as article about Mollies in a magazine... I think it was Aquarium USA.

I always thought that Mollies are a great beginner fish that was very easy to keep.

I had 3 sailfins, that perished while I was away and had someone doing my feeding for me. (I also have some recommendations about this if you ask...)

Anyways... a lot of people will put Mollies in tanks with other tropical fish... In the 75 degree area, when in fact, Mollies prefer it 78-82 degrees. Anything less than that makes them suseptible to disease or infection.

Also, they prefer slightly brackish water. I'll consult what the magazine said, and see if I can get back to you on the percentage.

I'll give you some more info also.

It's a cool article!

When I'm setting up a new tank, I always take some gravel from an established tank and put it in a bowl into the new tank.

Hope that helps!

thanks for that. will the molly fry adapt to there conditions as they were born in an(please forgive the grammer) un-brackish tank set-up. it looks like i have around 5 molly left which are a really good size now and they are now swimming freely without the need to hide from my child like giant danios which im hoping is a good sign, look forward to hearing from you.

Most aquarium fish can adapt to a fairly wide range of conditions, but to really thrive they need close to ideal conditions. That's why aquarists sometimes prefer single species tanks.

By the way, the article about mollies is in the January, 2009 issue of Aquarium Fish International. It also has a good article about algae, a subject that forces itself on most fish keepers at one time or another.