Monos Stealing Knifefish Feeders

[JerryINva]

Let me break down the scenario of our tank quickly before I describe the problem. We have a 50 gallon brackish cominity tank that consists of a group that gets along very well, without picking on each other or being agressive towards each other. Yet there is a problem when it comes to feeding time with 2 of them. Actually its 5 individauls, but 2 types of fish. We have a needlefish that has ruled the top of our tank for a very long time. We have provided him with plenty of feeders since the day we introduced him to the tank. He started at about 6 inches in length and is now well over 9. The problem is we aslso have a group of 5 monos that have grown noticably as well. The Monos have always been big fans of the flakes and blood worms we've fed the community, but now we're seeing a problem. They are starting to steal the needlefish's dinner. They each have gotten to about 4 or 5 inches from top to bottom. That might not be big for monos, but they were much smaller when they first were introduced to the tank. As a group they definatley dominate feeding time. They arent eating too much to the point where the rest of the crowd cant eat...but when it gets to the point that they are chasing/hunting minows and guppies that normally would be the knifefish's...its a problem. Our knife fish still gets about 2-3 guppies every other day, but we try to give him more. We must put 4-5 in a day, but the monos who are now getting over-grown, grab them before the feeders ever have a chance to swim near the knife for him to grab. Anyone have any ideas on how to keep the monos at bay until the knife gets his chance?

 

[JerryINva]

Ooops....sorry y'all. In the title thread I out knife fish...but as the article states, its needle fish.

 

[nmonks]

Greetings. Two things. Firstly, you shouldn't be giving a needlefish feeder fish. It's not their natural diet. In the wild, they eat crustaceans almost exclusively. Go check on Fishbase if you don't believe me. Fish and insects are a minor part of their normal diet. So consider feeding things like small crickets. Also try krill and river shrimp; supposedly also earthworms. They can be weaned onto dead foods, with care. If you do this, you'll have a much easier time getting food into the needlefish instead of the monos. Whitebait and lancefish are said to work best when thrown into the current so they "glisten" attractively.

As ever, if you must use feeder fish because you like creating extra work for yourself, avoid anything bought from a pet store, and definitely avoid rosy-red minnows and goldfish, both of which are categorically among the least healthy things you can give to any predatory fish for reasons that I (and others) have explained elsewhere on this forum. Only ever use home-bred livebearers or similar, and be sure and gut-load them first with vegetarian flake food to keep the vitamin levels right.

Second, in my opinion, needlefish and monos aren't really compatible. They're just so different in terms of activity levels. Monos are bullish, aggressive fish especially at feeding time. One might debate salinity preferences, too -- while freshwater needlefish are sometimes found in brackish water and supposedly even the sea, it isn't their normal habitat. Monos, by contrast, generally require around 50% normal seawater salinity to do well.

Cheers, Neale