Question about babies and lights at night

[mike.d]

History: I have a 10 gallon supershrimp tank on my desk in my home office. I started with about 65 shrimp in June of 2017. Everything has been going fine: Molting, algae, active shrimp, snails (nerites and MTS), and berried shrimp. I haven't put any food in the tank at all since I set it up. Over the course of a year despite seeing 7-10 berried females (sometimes 3 at a time) I only saw one larva which probably grew into the one juvenile that I saw a few months later.

Now, I see 10 larvae flitting around. The only thing I changed was I covered up my cable modem's blue flashing lights at night. The modem is right next to the tank and I figured the blue would be a nice "moon" effect for them. I've been covering it every night with a piece of cardboard for about a month.

Is blocking the nighttime blue light the reason I was finally successful with babies?

I know females will drop their eggs the first time they get pregnant, but I can't believe all of those berried shrimp were first time mothers. Shouldn't I have had multiple babies long before the 16-month mark?

[Mustafa]

You probably have/had a bunch of babies. They are tiny and tend to hide very well until they are quite large. That's what's responsible for what I call the "sudden population explosion" effect. Suddenly your population is much larger even though you never or rarely saw any larvae or babies. Did you try to count your shrimp? Do you have lots of hiding spaces?

[mike.d]

Thanks Mustafa. That makes sense. I do have a ton of hiding places.