Transferring One Aquarium To Another Aquarium

This is an article I've been meaning to do for a long time, about transferring one tank to another tank with minimal loss of the total ecosystem and making it as easy as possible to do. To simplify the start of this article, I am copy/pasting email posts that I answered in a recent thread on the AquaticLife Yahoo Group.

-----Original Message-----
From: AquaticLife@yahoogroups.com
On Behalf Of Lainey A.
Sent: Thursday, May 20, 2010 5:54 PM
To: AquaticLife@yahoogroups.com
Subject: [AquaticLife] Transfering tanks

I have to transfer my 37 g high tank to one that is less deep because my plants don't like the depth and I feel that I have tried every thing there is to try. My concern with this is - since this 37 is heavily planted, I can't vacuum too much and when I go to transfer all that filthy gravel to the new tank, I am worried about the water quality and that the fish will be harmed by it.

Should I rinse it? I realize that would harm any beneficial bacteria, but I think this gravel is going to have just as much bad bacteria as good.

I want to get the fish out of the tank, then remove the plants and this will stir up a major mess.

(ADDED IN FROM FOLLOW-UP EMAIL)
I forgot to mention that the gravel was expensive plant-growing gravel which is why I'd rather not have to replace it. I am afraid it cost something like $55 per bag shipped. But the plants do very well in it, and they don't do as well in the cheap Petco gravel I have in another tank.

Not sure what to do after that.

Thank you for any ideas...

Lainey
http://www.grasslandsgouldians.com/

-----Original Message-----
From: Lenny V. aka GoldLenny
Sent: Thursday, May 20, 2010 7:31 PM
To: 'AquaticLife@yahoogroups.com'
Subject: RE: [AquaticLife] Transfering tanks

Remember, that in a planted tank, you do not have nearly as many nitrifying bacteria as in a non-planted tank, since the plants are using up the nitrogenous compounds (ammonia, nitrite, nitrate are all nitrogenous compounds) as soon as they are released by the fish or decaying detritus. Further, unless one has a UGF (under gravel filter), the majority of the nitrifying bacteria will be in their main filter media, not in the gravel. There will be some nitrifying bacteria living on the top surface of your gravel, that is exposed to oxygenated water but any of the deeper gravel will have very little nitrifying bacteria.

Now, that said, there are a LOT of other bacteria, critters, etc., that make up an ecosystem that might or will be living in your current substrate, to help break down any detritus, so you want to minimize the ecological issues as much as possible.

Are you planning on using a new substrate in the new tank or the current substrate? That is the first BIG question. From your post, it looks like you are going to try and use the current substrate.

If this is the case, then you need to put some of the current tank's water (up to 50% or less, just enough for what you need in the holding tub), the fish, decorations and filter system in a holding tub/tank while you make the rest of the transfer.

Put most of the rest of the water in the new tank, leaving a couple of inches in the old tank with the substrate and plants.

What kind of substrate? Just gravel or do you have a more expensive plant helping substrate below the gravel? I kind of need to know this before continuing but I'll continue anyhow.

Next, pull up your existing plants cutting the roots as far away from the plants as possible when you have to cut roots. Put them in a separate holding tub since the root balls will have lots of dirt in them. If you don't have a separate holding tub, put them in with the fish and the dirt will setting to the bottom or be filtered out. The water will just be murkier in the fish tub.

Now, you are down to just your substrate. Depending on how your substrate was set up and hoping it is all the same kind of substrate and not a layered substrate... place a colander in the tank and using a slotted spoon or spatula or a kitty-litter box cleaner works well also, lift up the substrate and place it in the colander until mostly full. Lift the colander and let the murky dirty water drain and you can even slosh it around a little to get even more dirt/detritus out of the gravel. Place the colander in your new tank and slowly pour the gravel out onto the bottom. Repeat this as needed until you have transferred all of your gravel or as much as you need. The water will be murky but with no filter running, it will settle down... after you finish re-planting all of your plants which would be the next step.

Once the new tank has the substrate and plants in place, give it a little while for most of the murkiness to settle down. Once it has, then you can transfer the decorations, filter system and fish from their holding tub to the new tank. Once this is done, running the filter system will help to remove any murkiness that is still lurking.

DO NOT MESS WITH YOUR FILTERS DURING THIS PROCESS. In fact, it would have been best if you haven't fooled with your filter in the past week or so. If you did, hopefully you did proper filter maintenance (SEE MY ARTICLE ON THIS TOPIC) which preserved as many of your N-bacteria as possible and they should have recovered a full colony by now.

If your filters are really funky right now, then disregard the above and do proper filter maintenance, based on my article, to preserve as many N-bacteria as possible.

The reason I say this is that the plants might or probably will go into shock for a while and will not be using up the nitrogenous waste as much so your N-bacteria in your filter system will be relied upon much more and any N-bacteria you have will double their colony size every 24-48 hours so you will have to check your ammonia/nitrite levels daily for the week or two after this transfer to make sure you are not having cycling issues.

After you transfer your fish from their holding tub/tank to the new tank, also transfer as much of that water as possible into the new tank. This way, the new tank's water parameters will be the same as the tank they originally were in since up to 50% of that tank's water went into the holding tub/tank and most of the rest of the water went into the new tank before the substrate and plants. Then the fish and water from the holding tank went into the new tank so most of the new tank's water was just the water from the old tank. Hopefully, you won't have to add more than another 25% of new water to the tank which would be the same as when doing a 25% PWC under normal circumstances.

Minimizing any additional stress to the fish and plants is recommended during this transition.

Normally, turning off the lights is recommended when transferring fish but the plants will probably need the lighting to help them recover so you can turn on the lights but if you see the fish acting too stressed, then turn them off.

I should also add that if you are moving a non-planted tank from a smaller tank to a larger tank, now would be a good time to lessen the thickness of your substrate.  Many people, when first setting up an aquarium put in 2" to 3" of gravel on the bottom but in a non-planted tank, this amount of gravel is WAY TOO MUCH and just creates a haven for holding more detritus, making it much harder to keep the aquarium clean.  In non-planted tanks, you really only need enough gravel to cover the glass bottom... maybe 1/2" to 1"... just enough to mask the glass bottom and hold any detritus in between your weekly gravel vacuuming and 25% PWC's (partial water changes).  This much thinner layer of gravel makes it SO MUCH easier for you to vacuum compared to a 2" or 3" thick layer of gravel.   If you think you may want to add live plants one day, save your extra gravel and fill clay pots with a decent plant substrate, topped off by the gravel, as needed for your first plant endeavors instead of going with a thick layer of gravel on the bottom... just in case you decide you do not have an aquatic green thumb.  I still use clay pots in my 65G goldfish tank, mainly because too much gravel in a goldfish tank is just too much work at keeping clean and also because the fish are constantly uprooting the plants and it's easier for me to replant them in the clay pots and I can still vacuum the rest of the gravel really good while leaving the clay pots alone for the plants to use any detritus in them as plant food.  It works!

I think that covers it all and since I've been meaning to do a blog article about this topic, I'll probably use your Q & A in this thread as the basis for my blog article. Thanks for bringing this up!

Lenny Vasbinder
Fish Blog - http://goldlenny.blogspot.com/

Refs:
Personal experience
http://freshaquarium.about.com/cs/qa/f/faq0018.htm