Dithers, frozen bbs and dissapearing fry

[Corie Dora]

I have a pair of Cacs in my 35g planted community tank, whose fry became free swimming on Sunday. I first counted at least 20, but by the looks of it now, there may be less than half that many left I'm wondering if some of the other fishes in the tank are eating them, or if this is an expected mortality rate, since I'm feeding frozen bbs.

The other tank mates are

6 black neons
1 aeneus cory
2 Odessa barbs

The female has been really great at keeping everyone away from her 2/3 of the aquarium she's staked out; especially her nest. The cory is really attracted to the smell of the bbs, but I usually feed the other side of the tank at the same time as the babies to minimize the temptation to go over there. The same cory is also not very smart, and appears to have poor vision (much worse than most cories I've kept) and sometimes there will be a piece of food right beside him which he cannot find, so I'm not so sure its him.

Any thoughts?

Corie

 

[Apistt_ed]

The cory is definitely a great candidate for eating the fry. Actually any of them can be the culprit in this. The neons can overwhelm the mother when she's eating and pick them off one by one. The barbs depending on the can also do this.. but I would say that the most likely of the dithers is the corydora which can be quite active after the lights are out. Corys and plecos are still active nocturnally and with the female cacatuoides falling asleep, they can and will do anything to get at the young. Corys don't need great vision to find the fry. They are very keen with their barbells and will still skim the floor of the tank... so even if it seems harmless, it isn't. sorry to hear that you've lost some... if you'd like to safeguard the rest of them it would be best if you move the rest of the tankmates except the parents. good luck...


john

 

[Zapisto]

check for hydra
you will be surprise.

 

[Corie Dora]

Hydra, Really? I've read about them being a problem; I don't know that I've ever had hydra before....how does one go about checking for them?

When I set this tank up last year, I did use some 'live' river mud as one of the ingredients in my layered substrate. I had the tank runnning for few months before adding any fish, and there were all kinds of 'critters' in it. When I added the fish, the critters seemed to dissapear overnight; especially since I had a botia in there that first night. So its definately plausible that something like that is still lurking.

I've removed the cory (much to the dissapointment of my toddler, who calls him by name, and was very sad to see him gone this am) and the barbs, at any rate. The black neons are very timid, and stay under cover on the other end of the tank most of the time. They hardly even come out to eat, I'm very very doubtful it could be them. They don't even fuss over live daphnia.

Oh, also, the female keeps her fry mostly in beech leaf litter right now-I'm not sure if that means anything, but I thought I'd mention it.

Thanks everyone
Corie

 

[Mike Wise]

You are experiencing the normal attrition rate found in community tanks (and nature to a lesser extent where there are fewer predators/volume). If you want to breed a fish, use a breeding tank. Otherwise expect very few surviving fry.