Angel Pairs Partial to Caviar

All my pairs seem to enjoy eating both eggs and wrigglers. I start off with a good spawn between 200 and 500 eggs. By the time we get to wriggler stage 90% if not all are gone. They don't seem to eat the freeswimming fry. Everyday after the eggs are laid I notice some have disappeared. Any thoughts on why my pairs are doing this and how I can prevent it?

This could be a sign of young pairs they could do this for a few broods and then just become model parents with their fry care. If they continue to eat the eggs you may have to look at taking the parents away and rearing them artificially or purchasing a egg gaurd same as they use for discus, this allows the parents to tend the eggs but they cannot reach them for a snack.

Kim

There can be a number of reasons that a pair will eat eggs, wrigglers & even freeswimmers, but there are a few rules that I follow to give the fry the best chance of survival:

• Leave the lights on 24/7 as some parents eem to eat as soon as the lights go off or go on, some breederd just leave a light on near the tank but I have found with one pair I have this is not good enough, I need to leave the lights on in the tank 24/7.
  Water quality, make sure you sypon out a small amout of water & waist every day, some will eat if the water is not perfect.
  Feed: give them plenty of high protein food, alot of energy is used in laying & looking after fry, whitwe worm are very good for this or feeding live brine shrimp to parents.
  Stay away when they are laying, dad is no use if he is busy watching out for you whilst he is meant to be fertilizing!
  Small batches, be ready to pull parents of fry if only a small batch as the parents may decide not to bother raising them or may want to lay again resulting in the crearence of the small batch!
  Young pairs: They will need a few times to practice but by the third batch you would expect them to be getting the hang of things.
  If things are still going wrong then some clever tactics may be needed: will follow up tactics soon

In the wild fish are constantly competing for scarce food resorces. Those lucky enough not to become a food resorce themselves can allocate the food in four different ways, they can use it for growth, they can use it for maintainance, ie repairing damage and fighting off disease, they can use it for movement and finally any left over they can allocate to breeding, producing eggs or sperm, but also in spending time and effort obtaining and defending a territory.
Eating eggs/fry is therefore an excellent biological adaptation to less than optimal breeding conditions, efficiently recycling the nutrients ready to try again when conditions improve.
Angelfish are likely to eat their eggs if they are infertile, and their young if they are weak or diseased. They are also likely to consume them when there are lots of potential predators arround, and as far as the fish is concerned, that includes you! Confident fish make good parents, nervous ones are much more likely to turn on their young. If a fish rushes to the front of the aquarium when it sees you, it's likely to be a good parent, if it races to the back to hide, then it's nervous and a potential carnivore.

So, the secret to getting fish to parent raise, is make sure they are relaxed in their enviroment.
Lisa is correct to say that young fish can often take several attempts to get the hang of what they are doing, but I often find that even experienced, well bonded pairs, can take a couple of attempts before they succeed whenever they are moved to a new tank. I'm sure this is due them settling in to their new enviroment, but it may also reflect reduced fertility resulting from changes in the water chemistry.
In terms of lighting, I used to leave the light on when I was expectin eggs to hatch, and when I was expecting wrigglers to go free swimming, these seem to be the critical points when things are most likely to go wrong. I've tried leving the tank lights on, leaving a room, or reading light on, using small LED spot lights, and leaving the light off. Although I suspect, on occations using a light has helped, on other occations it seems to make the fish more nervous. So in general I don't use a night light. But it's well worth a try if you get persistent problems with a particular pair.
All my lights are on timers, and I think this is an important factor, the fish get to learn when lights off is coming, and gather newly free swimming youngsters together in readiness.
In terms of water changes, I don't do any water changes whilst the parents are guarding eggs or wrigglers, and only water change in the first couple of weeks of free swimming if the tank is looking desperately dirty!
I've found that at lower pH's, 7 or below, fish are often better at parent raising, but suspect this may have more to do with better hatch rates at lower pH's than an actual effect on the fishes behaviour.
I agree that the parental instinct is stronger with larger batches.
One other factor which is very important is position of the aquarium. My tanks are tiered 3 high, with the breeding tanks at the top. Adult fish seem much more relaxed looking down than when they have to look up. Whatever the height of the tank, avoid sudden movements or anything likely to startle parent fish. I'm very wary of taking photographs too close to a breeding tank, especially if the parents seem at all nervous.

kim554x wrote:This could be a sign of young pairs they could do this for a few broods and then just become model parents with their fry care. If they continue to eat the eggs you may have to look at taking the parents away and rearing them artificially or purchasing a egg gaurd same as they use for discus, this allows the parents to tend the eggs but they cannot reach them for a snack.

Kim

Thanks. They are all quite inexperienced young pairs, so that could be relevant.

Ghipsi wrote:There can be a number of reasons that a pair will eat eggs, wrigglers & even freeswimmers, but there are a few rules that I follow to give the fry the best chance of survival:

• Leave the lights on 24/7 as some parents eem to eat as soon as the lights go off or go on, some breederd just leave a light on near the tank but I have found with one pair I have this is not good enough, I need to leave the lights on in the tank 24/7.
  Water quality, make sure you sypon out a small amout of water & waist every day, some will eat if the water is not perfect.
  Feed: give them plenty of high protein food, alot of energy is used in laying & looking after fry, whitwe worm are very good for this or feeding live brine shrimp to parents.
  Stay away when they are laying, dad is no use if he is busy watching out for you whilst he is meant to be fertilizing!
  Small batches, be ready to pull parents of fry if only a small batch as the parents may decide not to bother raising them or may want to lay again resulting in the crearence of the small batch!
  Young pairs: They will need a few times to practice but by the third batch you would expect them to be getting the hang of things.
  If things are still going wrong then some clever tactics may be needed: will follow up tactics soon

Thanks Lisa. I have left the lights on with mixed results.

I have also tried doing daily water changes. Unfortunately my pinoy paraiba freaks out during water changes, so I tend not to do so many when she's looking after a spawn. I also try not to disturb them when they are spawning. Both my pairs have only had 3 batches, maybe things will improve.

Do tell me about your clever tactics please.

Pterophyllum wrote:In the wild fish are constantly competing for scarce food resorces. Those lucky enough not to become a food resorce themselves can allocate the food in four different ways, they can use it for growth, they can use it for maintainance, ie repairing damage and fighting off disease, they can use it for movement and finally any left over they can allocate to breeding, producing eggs or sperm, but also in spending time and effort obtaining and defending a territory.
Eating eggs/fry is therefore an excellent biological adaptation to less than optimal breeding conditions, efficiently recycling the nutrients ready to try again when conditions improve.
Angelfish are likely to eat their eggs if they are infertile, and their young if they are weak or diseased. They are also likely to consume them when there are lots of potential predators arround, and as far as the fish is concerned, that includes you! Confident fish make good parents, nervous ones are much more likely to turn on their young. If a fish rushes to the front of the aquarium when it sees you, it's likely to be a good parent, if it races to the back to hide, then it's nervous and a potential carnivore.

So, the secret to getting fish to parent raise, is make sure they are relaxed in their enviroment.
Lisa is correct to say that young fish can often take several attempts to get the hang of what they are doing, but I often find that even experienced, well bonded pairs, can take a couple of attempts before they succeed whenever they are moved to a new tank. I'm sure this is due them settling in to their new enviroment, but it may also reflect reduced fertility resulting from changes in the water chemistry.
In terms of lighting, I used to leave the light on when I was expectin eggs to hatch, and when I was expecting wrigglers to go free swimming, these seem to be the critical points when things are most likely to go wrong. I've tried leving the tank lights on, leaving a room, or reading light on, using small LED spot lights, and leaving the light off. Although I suspect, on occations using a light has helped, on other occations it seems to make the fish more nervous. So in general I don't use a night light. But it's well worth a try if you get persistent problems with a particular pair.
All my lights are on timers, and I think this is an important factor, the fish get to learn when lights off is coming, and gather newly free swimming youngsters together in readiness.
In terms of water changes, I don't do any water changes whilst the parents are guarding eggs or wrigglers, and only water change in the first couple of weeks of free swimming if the tank is looking desperately dirty!
I've found that at lower pH's, 7 or below, fish are often better at parent raising, but suspect this may have more to do with better hatch rates at lower pH's than an actual effect on the fishes behaviour.
I agree that the parental instinct is stronger with larger batches.
One other factor which is very important is position of the aquarium. My tanks are tiered 3 high, with the breeding tanks at the top. Adult fish seem much more relaxed looking down than when they have to look up. Whatever the height of the tank, avoid sudden movements or anything likely to startle parent fish. I'm very wary of taking photographs too close to a breeding tank, especially if the parents seem at all nervous.

Thanks Rob. I think perhaps the position of my tank may be a problem after reading your post. It is on a blanket box under the stairs. There's quite a lot of daily traffic back and forth. I think I shall try my next pair in the front room growout tank. This tank is on a shelf 5ft up in the alcove. The room is also rarely used.

I will let you all know how this goes when the time comes, but I suspect it's a combination of several different factors.

No not that sort of position I've put my zebra and smokey lace in the growout tank on the shelf in my front room. This pair have eaten every one of their spawns. I'm wondering, if as Rob suggested, where the tank is positioned will make a difference. I will let you know the outcome when they spawn.