Basic Fry Care Questions

Hi,

I have shiners (rainbow and sailfin) and dace (mountain redbelly) in a 40 gallon tank. When, and if, fry come this spring:

1. Should I seperate the fry from the adults and put them in a separate, or is that an almost impossible task considering how many are born? Should I just make sure the little ones have plenty of hiding places?

2. How and what do I feed fry if I need to separate? How and what do I feed them if I leave them in the main tank?

Any advice or instruction welcomed. Thanks, all.

You may never see fry because all fish in the tank will eat any eggs they find immediately. I know that rainbow shiner eggs are nonadhesive. If spawning takes place over coarse pebbles or pea gravel some eggs may actually survive and hatch, and then they become free food to the first takers. I guess I'm pessimistic about survivors in a community tank, hopefully I'm wrong.

I have found fry swimming near the surface in a single-species tank of 6 well-fed Pteronotropis merlini, which were considered Sailfin Shiners at one time.

I removed the fry. Feed egg-yolk suspension, infusoria / paramecium, and/or Cyclopes-ease, and then newly hatched baby brine shrimp.

The temperature can be higher than the spawning or hatching temperature, 74F to ?80F.

Edited by PhilipKukulski, 03 February 2009 - 08:41 AM.

I guess I'm pessimistic about survivors in a community tank, hopefully I'm wrong.

Does anybody have any success stories about fry and community tanks?

I have found fry swimming near the surface in a single-species tank of 6 well-fed Pteronotropis merlini, which were considered Sailfin Shiners at one time.

Oops, I have flagfin shiners (Pteronotropis signipinnis), not sailfin.

Does anybody have any success stories about fry and community tanks?

I'm by no means a guy that breeds or attempts to breed (with one exception). I have have now had many surprise spawns in community tanks and all failed. The eggs or the fry are eaten. I will never expect any success from a community tank but I'd guess if the conditions are perfect with exactly the right species and you intervene at exactly the right time, you might be able to save a few fish.

I have had Heterandria formosa, the Least killifish in a tank with some minnows and a few floating yarn mops and a little hornwort. I kept the Formosa for 3 months, and then I caught them all and sold them. Three months later, I caught all my Formosa and sold them. Once again, I caught all the Formosa and sold them. And then, I caught all the Formosa and sold them. The fourth time was the charm, I had caught and sold all my Formosa.

Livebearers have the advantage of no egg, and no helpless larval stage. And I have faith in formosa to be prolific and resourceful so I'm not surprised.

Does anybody have any success stories about fry and community tanks?

I had a 30 gallon brackish tank with Sailfin mollies, rainwater killies, F. confluentus, and Diamond killies. The Diamond killies laid eggs in the tiny holes of fossilized coral rock and i figured none would make it as the Diamonds were constantly trying to suck them out. But when doing a water change I found four fry in some floating plastic plants. Not exactly great success numerically but interesting. Raised them in a betta bowl on crumbled flake food till they started changing shape enough to be sure what they were. Key is a place for eggs to be out of reach of fish, snails and bugs and places fry can get into that predators can't to well. Well fed fish certainly helps too.

A number of folks here including myself have also made"nests" from flower pots, bowls, plastic paint roller pan inserts some covered by a plastic grid and overlaid with small stones so you can harvest at least some eggs. A small tank say ten gallons with a piece of plastic grid from the fabric or hobby shop set up a couple of inches off the bottom can be used to give eggs that settle through a safe haven till spawning is over and adults can be removed. Can put a pile of stones for a nest or a bunch of plants loosely scattered on top. Make sure the grid fits snuggly or fish can get under or stuck trying.

It should be possible to catch some of the fry automatically. If you set up an intake, overflow, and sump right, fry would be carried from the main tank, and have a calm space to hang in the sump. Look at the way pet shops have wet/dry trickle filters set-up to get the idea.

For some reason I find rainwater killie fry particularly adept at avoiding predation and more importantly, able to find sufficient tiny food to survive and grow in community tanks. Of course these are old, well established heavily planted tanks. I doubt they'd do as well in a more barren tank.
I also regularly retrieve rainwater killie fry from my canister filter where they seem to thrive. I have one in there now which has been there a long time. It's not even really a fry anymore, more a small adult.

For serious breeding of the shiners and dace, I recommend setting up a seperate tank. After observing spawning behavoir for a few days, remove the adults and raise the fry in the breeding tank. Check out this old thread to see how I did it. spawning southern red bellied dace