Hi Chinmo,
sorry to hear about the seahorse babies falling like flies. don't give up.
listen, these are some of the time markers for seahorse fly husbandry. hope this can help you.
day 2-3, lots of death, food supply insufficient
day 3-7, lots of death, food lacking in nutrition
day 7-14, death can be caused by poor filtration & parasite built up, poor waste management.
day 14-30, seahorse babies should gain in size & weight by now, single or multiple deaths, poor food distribution assuming the factors from day 7-14 taken care of.
if you clear the first month,good, you have more or less establish a feeding & care program.
the rest will be easy & other time markers will be the 2-3 month & 6 month.
btw, never put less than 60 babies in 100ltr of water.
go for bare tank system & watch the food quality.
happy seahorse keeping!