my betta who does nothing but sit on his plant all day blew out a
giant bubble nest yesterday. I put the female into the tank at this
point (she was ready to lay eggs). Is there a way of knowing if she
actually did lay eggs ?
A: It is not always easy to determine with a 100% accuracy whether bettas have spawned and are done. Because we cannot watch them 24/7, spawning oftentimes occurs while we are away. We human have to pay bills (well darn it), so we go to work, or to school. We humans also have to catch some zzzzs now and so often, so we go to bed. Meanwhile, bettas have only one thing to do: spawn. If you have been leaving your tank lights on, they might be in the process of spawning all day and all night for several days. Let me rephrase this: "in the process of spawning" here encompasses ALL spawning related activities (not just the actual laying of eggs), including (but not limited to LOL): Blowing bubbles, arranging them into a nest, changing our minds about nest location, moving nest under a plant, rearranging bubbles, blowing more bubbles, eyeing out the female, swimming to the female and hunting her down to abuse her some (just so she'll know who the boss is), displaying for her, flaring, nipping, biting, going back to the nest, changing our minds about its location again and moving it back to the cup, getting distracted by the damsel once again and letting the nest fall apart, rest for a moment, eat a few frozen brine shrimp, get back to work, build a new nest even nicer than the first one, etc...
Meanwhile the damsel is quite busy herself: Hide in this plant, dodge an open jaw coming at her, zoom to this corner, dodge another bite, run to this plant and hide, not move at all, (ah if only I could stop breathing maybe he wouldn't notice me here) hide, hide and hide some more, get daring and pop out for a second to eye out the nest (no, its' not quite to my liking yet, needs a few more bubbles here), dodge another bite and (outch! got me this time) lose a scale or two (darn it! those were my designer scales, too!) and zoom to the other corner of the tank... etc.
At some point (and you can bet it will be while you are at work, at school, sleeping, or even blinking LOL ), the two decide to get on with it and start the actual spawning. Spawning itself may last from 1 to 4 hours on average. All the while the female releases many small batches of eggs (6 to 30 eggs at a time). As you know, male and sometimes even female, will then place them neatly into the bubble nest.
Once the female runs out of eggs, she is no longer desirable (figures!) and the male betta runs off with his 20 year old assistant LOL. No, wait, this is men. Right. Bettas do not run off with their assistants (but they would if they had one LOL) they simply lose all interest in the female and now focus on the nest. If the female so much as blinks, they will chase her and beat the daylight out of her. Hence the need to remove female right away after spawning has been completed.
Now to your question (yes yes I WAS getting there):
It is often hard to tell if the eggs have been laid, unless you actually witnessed the spawning occur and watched it. So how is one to tell if they are done and female is to be removed? Look for the following:
Remember: If at any time during spawning, the female life becomes endangered (too many scales have been lost, especially the designer ones LOL, fins have been torn too much, female is hyperventilating and possibly lying on her side), then you must remove her right away. Always have Bettamax on hands to treat injured fish so to prevent infection and losing your priced breeders.
Goodluck and have fun! (and don't blink, or your bettas will spawn! LOL)