Which Are More Aggresive, Scats Or Monos?

[the_evil_duboisi]

The prices of both have dropped, so I was thinking about a 70 gallon with one species with some archerfish. The thing is, I don't want to take chances. I know both can get big(The biggest scat I saw was 15 inches, mono 9 inches high)

WHich is more peaseful. On account of my experiance, I saw some scats with some puffers tear up a live goldfish, with the archers and monos just picking out the flying bits. Still, you can't beat personal experiance!

Ted

 

[nmonks]

I'm trying to think who in their right mind would feed goldfish to puffers and scats... one eats shelled invertebrates the other eats plants and organic detritus. Not one of them normally eats fish! Marine fish are known to get sick when fed goldfish (read Bob Fenner and others on the topic) so it's a STUPID thing to do as well as pointless. Scats will eat anything of course, but they mostly take crumbs from around the feeding activity of other fish. When I kept them with archers, they were always stealing the crickets the archers the archers had knocked in the water! But a healthy scat is a scat that's eating greens morning, noon, and night.

Anyway, I've kept 1 archer with 4 monos, 1 silver scat, and 3 shark catfish and had no problems. I know people who have had problems with small groups of monos though. Depends on the tank. I kept mine in a 200 gallon system, so all the fish had plenty of space.

I'm amazed by the sizes you're reporting! Wild monos and scats certainly get big, but aquarium specimens tend to stay fairly small. 15 cm long seems to going rate for monos, and maybe 20 cm for scats. A 15-inch scat is about 40 cm by my reckoning, and not many specimens get that size even in the wild!

To answer your question though, monos tend to be more pushy than scats. Scats are mostly greedy rather than aggressive, and so while they may annoy other fish, it's because they're more "in your face" at feeding time. Monos can be territorial, it seems, and may form pairs under certain conditions (see Schaefer in the Aqualog book). Never seen this myself, but that doesn't mean it doesn't happen!

Regardless, a 70 gallon tank is borderline for either. If you possibly can, learn to recognise Monodactylus kottelati and Selenotoca papuensis; both are "dwarf" species and you could keep large groups in a 70 gallon tank side-stepping any potential problems with behaviour.

Cheers, Neale

 

[kanzaris]

Hi

For me Scats have always been worse then Monos, but I had my fair share of problems with Monos as well. I had 7 Monos in my 150 gal tank and they were stressing the other fish. They didn’t pick on any other fish only fighting with themselves. Since I gave three Monos to Fella things have calmed down with the remaining 4 Monos. It’s a shame because they are both beautiful species of Fish. I think everybody has different experiences.

Sabby

 

[the_evil_duboisi]

Wow! It all depends on the indivisual fish(es)!

I'll consider it more then....But I take it archers are very peaseful? I want to keep one, my brother loves them!

 

[kanzaris]

Wow! It all depends on the indivisual fish(es)!

I'll consider it more then....But I take it archers are very peaseful? I want to keep one, my brother loves them!

Hi

(Wow! It all depends on the individual fish(es)! )

I personally think so. There will be people who will disagree with me of course.
I started of with a 75 gal tank. The advice from my LFS was so bad, that I ended up with 2 orange Chromides, 1 Archer, 2 Monos, 2 Scats, 2 Columbian Catfish and my GSP and 2 Knight Gobies. Most of the Fish where going to get far too big in a short amount of time, they needed different salinity’s etc. etc. I know it’s my own fault for not doing my own research but I trusted the LFS as I have known them for a few years now but mainly for Cichlids. The Archer was fine by himself; the 2 Scats nearly killed themselves, so I brought them back, and the same with the Monos, when I had only the one Mono left he became very scared and would hide in a corner. As soon I got my big tank he was back to his normal self. I added 4 more Archers and 6 more Monos, and there was one little Scat (about 2inch) left in the Shop so I thought I can’t leave him there so I took him.
As soon as I put him into my tank he started on all of my Archers and Monos. The Monos& Archers are all about 4-5 inch. I gave him a few days to settle but that little thing coursed havoc in my tank, so I had to take him back. The Monos constantly chased each other so Fella had three and things have settled down now.
I think as well as doing your research and getting the right fish there is a bit of luck involved.

Sabby

 

[CFC]

Monos i have always found the more the merrier to keep aggression down and especially with the sebae monos which become anti social war machines when kept in groups of less than 3, i currently have 6 monos in a 150 gallon and apart from the usual pecking order disputes they are peacefull.

Scats will attempt to eat anything new added to the tank, its not so much aggression than just a need to test every thing they come across to see if it can be eaten to satisfy their ravenous appetites, over the years i have lost a few fish to stress caused by scats constantly nipping at them in the first few hours of being introduced to the tank, ive found the best soultion is never add anything that is smaller than the largest scat. I've always kept scats in groups of 3 or more so i dont really know how they will behave in smaller groups over the long term but in a group one will quickly become the dominant fish and will bully the others at feeding time.