Moving small fish into a big tank - advice needed

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wallskm

Gambusia
MFK Member
May 30, 2017
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I've made a post over on the cichlid-forum but would like to get some input on folks with large tanks as well. I need some advice on when to move my Tanganyikan cichlids from my quarantine tanks over to my main tank.

I currently have 13 moba frontosa at about 1.5 to 2 inches in a 10 gallon quarantine tank. I do daily 50% water changes and feed them NLS cichlid 1mm sinking pellets. They seem healthy and eat the pellets whole without difficulty.

I have 10 black calvus and 9 leleupi in a 20 gallon tank. These guys range in size from 1 to 2 inches. They get a 25% water change daily and also seem healthy and are fed the same pellets. The largest of the calvus eat the 1mm pellets whole without issue. The remainder of the fish cannot and require crushing of the pellets to eat.

All fish have been in quarantine for 1 week so far. They will be moving to my large aquarium (I think it's about 800 gallons of water when subtracting the decor) when appropriate. My concern is that the tank is so large and the fish so small that I worry they may not get the food they need. I'm particularly worried about the smallest of the fish that need the pellets ground up to eat. They find the food easily on the barebottom 20 gallon tank but will have more trouble in a large sand bottom tank.

I could use some advice on when you think it is appropriate to move them over to the main tank. My original plan was to quarantine for 2 weeks in the small tanks but should I keep them there longer? The main tank is empty right now. These will be the first fish going in. It is well-cycled and I continue to add ammonia to it every other day. When it's time to add fish, I'll have to do a giant water change to prepare.

I think my frontosa will do fine in the large tank. They already are conditioned to come towards me at feeding time and eat the pellets before they hit the bottom. I don't really like them in such a small tank for very long. Thoughts? And thanks!

For more information on my tank please see the linked thread below:
https://www.monsterfishkeepers.com/forums/threads/newbie-1000-gallon-help.688239/
 
This sounds like an amazing tank, if I'm understanding the question, this is what I'd do:

1. Make sure new tank is fully cycled and everything is ready to go before adding the fish.
2. Make sure all fish are 100% healthy (sounds like you're doing a great job at that).
3. Make sure nothing is too small to become food.
4. If everything is perfect add all at the same time.
5. Enjoy :)
 
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I guess my main question is: Can a fish be too small for a tank?

I just don't want the small fish to have trouble locating tiny fragments of food when I drop it in. This is a difficult topic to search on. Looking for posts about small fish in a big tank returns posts regarding big fish in a small tank.
 
My concern is that the tank is so large and the fish so small that I worry they may not get the food they need.
Hello; My take is this is not going to be an issue. 800 gallons is big for a tank but still tiny when compared to a natural setting. I will say it will not be a problem.

My original plan was to quarantine for 2 weeks in the small tanks but should I keep them there longer? The main tank is empty right now. These will be the first fish going in.
Hello; Interesting. Being the first fish in the tank they cannot introduce disease or parasites to any other fish so spreading disease/parasites to a tank of healthy fish is not the issue.

I would keep them in the QT for a total of 4 to 6 weeks anyway. The why is if the fish do turn out to have disease/parasites it is so very much easier to treat in the smaller tank. Also the big tank will not be contaminated.
Can a fish be too small for a tank?
Hello; in general a big NO. The only issue I ever have with small fish is when they can be sucked into a filter intake. With fry I make screens over the filter intakes.

Hello; What a nice problem to have.
 
I would keep them in the QT for a total of 4 to 6 weeks anyway. The why is if the fish do turn out to have disease/parasites it is so very much easier to treat in the smaller tank. Also the big tank will not be contaminated.

This was my reasoning for the quarantine. Thanks for the advice. :)
 
I have a cichlid fry about 2 months old , about 2cm, in a 6x2x2 tank with my bigger cichlids all about 5-8 inches and another 8 adult syndo cat and he still managed to stay alive so I guess he has a way of finding food

I don't even crush the pellets. Feeding hikari gold bio + and hikari gold sinking small pellets

1 thing though growth is very slow
 
sounds great I look forward to seeing pictures of them in their new home. Hopefully it will work out well as it does most of the time. I wish you better luck than I had with the leleupi getting eaten.
 
They should be just fine and will put on size more quickly in a large tank. I really wouldn't worry about them not being able to find food.
 
Glad to hear the size shouldn't be a big issue. Would you keep them in the smaller tanks for longer than 2 weeks to avoid introducing any infection to the larger tank?
 
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