Perfectly Round White Spots On My Aquarium Glass

[LibraSunLibraMoon]

Despite a true siamese algae eater in my 20 gallon freshwater tank, I've had a recurring problem with algae on the aquarium glass.  Last Saturday, I decided to refresh my aquarium.  I moved the fish (the algae eater, 3 corycats, and 3 neon tetras) to a temporary container, washed the gravel and decorations multiple times, rinsed the Biomax and Eco-Bio block, and replaced the carbon and foam before refilling and reloading the tank.  I used a bottle of Tetra SafeStart to immediately restore a healthy bacteria environment.  On Monday, I purchased 5 new neon tetras from a local pet store chain.  I did not quarantine the fish, I just rested them in a container of water from my tank for about an hour before adding them to my tank.  Then last night (Tuesday), I suddenly noticed small groups of perfectly round white spots on my aquarium glass.  I have attached two pictures.  The white spots are circled in red.  Does anyone know what these spots are and whether my fish are at risk??  Your advice is greatly appreciated.

BTW, all of the fish appear healthy and happy.  The new neon tetras are shoaling with the old neon tetras, the corycats are more active than ever, and the algae eater is hanging out as usual.

 

Edited May 12, 2021 by LibraSunLibraMoon
Figured out how to add pictures. Also edited wording.

[MAC]

Are these 'spots' on the glass or are these corydoras eggs? From the pictures it looks like eggs. 

[Colu]

4 minutes ago, MAC said:

Are these 'spots' on the glass or are these corydoras eggs? From the pictures it looks like eggs. 

Definitely Cory eggs

[LibraSunLibraMoon]

MAC and Colu, I've probably had the corycats 5 years, but never had those round white things on the glass before.

But conditions in the tank may not have been good enough. Thanks for your help! I'll read up on how to care for the eggs.

Edited May 12, 2021 by LibraSunLibraMoon
Corrected spelling and wording

[Andy's Fish Den]

The major tank cleaning probably triggered them to spawn. They could have spawned before and you just never knew because either they or something else in the tank ate the eggs before you spotted them. 

[LibraSunLibraMoon]

Thanks, Andy's Fish Den. You make a good point. Also, I had alot of artificial plants in the tank before I did the refresh. When I did the refresh, I only put back a few of the shorter plants.  I have a much better view inside the tank now.