After deciding to try a new species, I ordered 5 neon gobies, Elacatinus oceanops, and put them in the quarantine tank with a few PVC pipe fittings.  I fed them a lot, and they all seemed to get along well. After a couple of weeks, I noticed one of the fish staying in the PVC! Sure enough, it was a male guarding some eggs.  It was the biggest fish in the tank, and that surprised me since I was told that the biggest one would likely be female. I did not know which one was the female at first, but then I noticed one of the fish had a large abdomen almost all the time. I made attempts at hatching the eggs, and that was fun, but the babies did not live for many tries. Then I noticed one of the smaller gobies was getting picked on, so I removed it and another small one to another tank. They got along very well, and pretty soon, they had eggs, too. The fifth gobie disappeared.  I never knew what happened to it.
Feeling pretty good about getting two pairs of spawning fish out of 5 purchased, I began serious attempts to hatch eggs and raise the larvae.  I tried a glass tank, tigger pods, rotifers of course, and all kinds of things.  I even bought a small UV filter thinking that bacteria had killed one of the batches.  Then I just got lucky.  A black round tub, and about 7 gallons of water, and careful food administration did the trick. Just rotifers, new hatched brine shrimp after about a week, and the smallest size golden pearls, just a dusting daily, along with careful neglect and a little circulation at night when they were sleeping.  I did use a night light and a bright light in daytime. That made it more fun because I could actually see the little transparent larvae for the 4 weeks it took for metamorphosis to occur.

Tried my patience, but I was rewarded with a tub full of irridescent blue-green striped fish!