u/Humble_Improvement23

About a year ago, I kept a tank gifted to me for Christmas. It did pretty well, they lived for about 6 months and I was confident I would have a strong colony.
My seamonkeys were breeding, had multiple females with eggs. But it felt like no babies ever survived. Numbers dwindled until I had 1 female, and she sadly died too.

So my question:

How can I keep a tank alive without purchasing extra equipment? (Other than a warming lamp, because I live in canada.) And, what could I have been doing wrong?

The image linked is my old tank for reference. I even finally had algae growing, but as you can see they were already dwindling ;-;

Any advice is appreciated!!

TLDR; seamonkies died, how to make them not die