How do I have better success with my nanolutea fry

[Hybridfish7]

I've had 5 batches of eggs from my pair so far, only two of which resulting in fry. The first batch only had a little less than 100 to start out with, resulting in around 50 living and getting to a decent size with the parents, I sold off 25, the remainders got picked off by the parents until there were around 5, then 1, then that individual got stressed to death by a tankmate in a separate tank.
Second batch had around 200 to start out with, not sure what happened but once they hit a month old the population just dropped to 40, I pulled all but two, let's just say of that entire batch only 3 are alive (one from the group I pulled, one that's still living with the parents and one of the two that I left but pulled to a planted tank)
I will be honest, I am not the best on getting them baby brine shrimp but I do try to feed at least once a day and give them something to graze. Is my main issue just getting them food/growing them fast enough to where they grow out of that juvenile sensitivity?

 

[Alexxxxsv14]

Best rate is to syphon fry and grow out separately in a tank by themselves. Clean water and sufficient food for best results

 

[duanes]

In nature if only 1 or 2 survive from a spawn, that is considered a success.
If you are able to save 25 or more, I would consider that very (almost overly) successful.
Often when large numbers of fry are saved, many are weaklings, and not the best representatives to further pass along genes.
I realize many breeders want to save as many as possible, but to me, not always the best idea.
Allowing some sort of survival of the fittest to take place (however anthropomorphic) gives some semblance of a better selection.

 

[Hybridfish7]

Would the stock then be considered phenomenal genetically if dozens survive in a natural setup?

 

[duanes]

Below is taken from a in Ad Konings book, "Cichlids from Central America", and deals with the evolution of cichlids in general, although in this example, he uses survival of fry from P managuense.

"from the total of fry one pair of cichlids (or other organisms) produce during their entire life, on average only TWO will eventually reach maturity and replace their parents in the population. All other offspring, sometimes numbering in the thousands, will fall prey to the environment. For those who think that from a successful species a few more may survive, I give the following calculation. Imagine one pair of P managuense in Lake Nicaragua. This lake has a surface area of 3,000 sq. miles and has an average depth of 40 ft.
The volume of this lake 96,000 trillion liters of water.
A mature pair of P managuense must have a volume of at least one liter.
Assume further that this pair will spawn only twice in their lifetime and produce 1,000 wrigglers in total.
if their is no loss of fry these these will be mature in 2 years and require a volume of 500 liters.
These thousand mature form 500 pairs, and each produce another 1,000 fry in the next two years, yielding 500,000 adult cichlids in four years. If we continue in a similar fashion the lake will be filled to the brim with P managuense in just 10 years.

Admittedly, the survival of all fry is not feasible. even under artificial conditions, so let us calculate what happens if just 2 grow to full maturity..
This means 3 adult managuense after 2 years, and ten in 8 years. If we continue we find that the lake will be completely crammed in 153 years.
Some cichlid communities may exist for millions of years. It must be clear that only 2 descendants of thousands of fry born from 1 pair of cichlids reach maturity, not even 3."

 

[C. Breeze]

Hmmm. He is definitely is making the math work to prove his point. I remember in 9th grade my geometry teacher MR Ionedes, an import from Greece, demonstrated a mathematically correct proof of the theorem 1=0. But clearly, it does not.

because successful pairs not only have to replace themselves, but they also have to replace unsuccessful mature individuals.

so the reality is that some spawnings produce a significantly larger number of offspring that reach productoce age than other spawns. Which for instance get consumed in one bite as wrigglers.

are we to assume , as has ad koenings, that the population of Managuense in lake Nicaragua has been static low these thousands of years ? Or isn’t it more reasonable to asssume that like every other population of fish in the planet it has had booms and busts.
I mean- the carrying capacity of the lake is going to vary according to the climate, and other controlling factors year to year and especially decade to decade or half century to half century- And then how that carrying capacity is distributed across species will also vary according to what organisms the situation favors.

but again- he does make the math work to support his position

 

[dogofwar]

I think the biggest mistake folks make is that they put new fry into new tanks. To raise more fry, it's best to remove them as eggs or wigglers. I use a plastic jug I got from the Dollar store to raise them to free swimming / eating for a couple of days. I feed a mix of infusoria (green water / gunk in the window of my fishroom) with decapsulated brine shrimp (from YourFishStuff) and Golden Pearls and add or siphon a little water each day.

After a couple of days, I add the container of fry to a 15g tank that has been up and running for awhile (I remove the fish that were in it, of course). I continue to feed decapsulated brine and golden pearls and change a little water each day or two. I have sponges and Poret filters in most tanks which also feeds fry.

I prefer to watch parents raise fry. One way to encourage them to be better parents is to have another fish in the tank (e.g. a goldfish) that can take a licking and continue swimming. Or put another fish behind a divider.

 

[fishguy1978]

With my G. Brasiliensis, I remove fry when they are wigglers and place them in a fry box with some susswassertang and guppy grass. Any free floating live plants will work. I wait until they are free swimming to start feeding them. I feed micro worms and powdered fry feed. I will also drop large pellets in for them to snack on. When possible I also try to feed 2-3 times a day. Out of the first spawn I have lost less than a dozen, most were my fault. Batch #5 are in the sump hatchery.

 

[fishdance]

The simple answer is the baby fish need more food available, they have little reserve when small once their yolk sac is depleted.

Find a way to feed more frequently without overfeeding and you will get more survive.

I culture infusoria in staggered rotation so there is a new batch ready each day. Drip feed over a slow air stone as I have a full time job and not much time. The baby fish quickly learn where to sit to find food. You can't beat live food as young fish instinctively know it's food and it won't pollute the water for days if you do over feed.

If your tank is big enough, you can do same with artemia, but the salt can build up and it's easier to overfeed.

Microworms will live underwater several days. Live plants as some have suggested. If you leave babies with parents (I never do) then you can feed the parents who will deliver the food to fry.

Or if you don't have the time, decide not to breed. There isn't any point in sacrificing your time to raise fish for no real purpose