Your hubby is uneducated and lacks experience with the growth habits of hardy hybrid small varieties of hardy water lilies. The small and dwarf varieties have very little spread, spread slowly, and grow only shallow 2 to 4ft deep. In new hard bottom ponds the dwarf and small varieties of water lily struggle to spread very much due to the hard compacted bottom material. Medium and large varieties do grow deeper and spread somewhat and often much faster than the dwarf and small varieties. First as in buying the right tree choose the proper specie or variety so it does not grow too tall or stay too short. Maybe hubby only has experience with the wild types of water lilies that are often rampant and grow deep 6-10ft depending on specie/variety. You will see in the links about two articles in Pond Boss magazine (issue and year) I wrote all about water lilies in ponds. There is a lot to know. Definitely all water lilies are not the same just as all flowers, all trees, all people and all illness are not the same.
Lilies
https://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=110943#Post110943Beneficial Pond Plants
https://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=440475#Post440475Read through our archives for other good pond management information and lessons to be learned.
https://forums.pondboss.com/ubbthreads.php?ubb=postlist&Board=22&page=1Unless you stock only a few select species or varieties of fish you will need to harvest some fish maybe lots of them to keep the pond in balance so catch and release(C&R) is fun and exciting. Normal fish reproduce so ponds can easily become overpopulated with small slow growing fish if fish are not harvested and managed properly. We here are to help you with that.
Also read in the LMBass Archive about producing hook smart or hook shy fish. C&R in a small pond this becomes more of a problem. Learn about it, how to reduce it, and what are the best species to stock to minimize hook smart fish.
https://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=255372#Post255372Good pond management is not simple and there are lots of things to know. Do you subscribe to Pond Boss Magazine? It is a very little expense and gives great pond information in exchange for all the expert information you learn here for free. There is a good algae control section in the Archives. FIRST know what you have as in an illness then treat it.