Congrats!
It can be 2 to 3 weeks. Make sure ya grab your coffee before turning on the lights. Your best bet is to get the coffee and when the sun starts to come up enough to affect the tank... turn on the tank lights a little early to see the whole thing.
If you are out of town when it happens the brood shouldn't be big enough to affect water quality where this is his first pregnancy. But now that they've figured it out, the next pregnancy could happen the day he releases the fry.
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