Adopting some fish. How should I do this?

Dear gurus,
A person at my workplace is now leaving. He tried to sell his fish tank but didn't get any takers. He now sent an email around saying that the fish have to be adopted by somebody TODAY or he will kill them and put away the aquarium. I already have only 4 harlequin rasboras (no other fish, but two nerite snails) in my 63 l tank, so I'm thinking that 6 more would fit. However, I know that adding six at once would most likely wreak havoc on my tank, so what should I do? I have a little nano-cube which I was thinking I could add two into, and then put four into the main tank. The nano cube would need many water changes to keep the parameters balanced I would guess. I asked the guy if he could bring an extra bag of water from his tank so that I can fill it partially with that, and I plan to take a rock from the main tank and put it in there. Daily changes or every other day would be ok? 20%? And I do some more frequent water changes in the main aquarium as well for a while? Then in a week or a bit more, if all of the water parameters are ok (I have a liquid measuring kit) I could add the two into the main tank? Or should I wait longer? I just can't stand the thought of them not even getting a chance

Thanks
C.

 

Oh, I guess I forgot to say that the 6 fish he wants to get rid of are also harlequins

 

63 gallon tank? You could fit 20 rasboras in there no problem.

 

63 liters, if I read the original post right. No, you can't fit 20 anything in there (except shrimp and some snails). I'm not sure where the 20 is coming from though.

Adding six harlequins to that tank might be overcrowding it a bit; I think I've read that they need more space than that. Other members may have more info there.

What you really need from that guy is his filter, or at least the insert. If he's just closing down the tank, get him to put the filter insert in a container of TANK water. Offer to pay him fair market value for the filter, if he'll accept; otherwise, you'll either need to wedge his filter media into your existing filtration or else buy a new filter to run it in.

As long as you keep it wet, the bacteria should stay alive; then you can add the filtration to your own tank along with all the fish. You shouldn't have any serious problem with the parameters that way.

 

Huh, do I get this right? You've got a cycled 63 litre tank with 4 fish and 2 snails? And you're asking if 6 others will fit ? If so : sure !!!! The fish will feel better in a larger school (there are 3 kinds of harlequins by the way !!!!). I'd would certainly do that (have a lot of adopted ones). Try to get is filter and tank as well. You'll be ready for MTS soon (multiple tank syndrom) hahaha

 

If you get some Tetra SafeStart, that will up the beneficial bacteria in your tank...make sure to monitor water parameters closely.
Can you get the tank from him? Not sure how to advise as to QT...how long has he had these fish? Has he noticed any sign of disease?

 

Sorry my bad. Yes 63 liters is a tad small. 10 rasboras will need about at least 20 us gallons, that is 80 liters.

It's risky but 10 in a 63 may be fine if you have over filtration using a canister and more frequent water changes, rasboras grow to adult size of 2 inches.

 

Yes, 63 litres not gallons. No I can't buy the tank from him unfortunately. It's way too big for my apartment (around 120 litres). My filtration should be quite good as far as I understand. I have a Juwel sponge filter, and it should be fit for up to 100L according to the manufacturer.

He's had the fish for a long time as far as I understood. A room mate moved out a while ago, and left the tank behind for him. He had a lot of fish however, and they have been spread around to several different people, so somebody else got the filter. I only got water. I don't have any tetra safe-start (I'll go and buy some tomorrow), but I have something called . The guy at the pet store told me to buy it and use it after some antI bacteria treatment I used a while ago to make the bacteria in the filter get back up and running. It says on the bottle that by adding it you can add fish after just 24 hours when starting a new aquarium, and once per week you should add some. (I don't add it on a regular basis though. Only that time after the treatment.) I added some of this now. The reason I thought of the quarantine tank was to be sure not to add too many at once and cause massive death in the tank.

 

While it would be overcrowding your tank a bit, I guess it is preferable to having the fish killed.

I would add all the rasbora's to the 63l tank and either add a bottle of SafeStart or just do daily water changes until you grow enough bacteria to handle the additional bioload (assuming you cannot get his filter media).