Things that reefers can do to help save themselves money

[howdy20012002]

I thought I would start a thread that would allow members to share their wealth of knowledge with others in ways that they can help save a few bucks.
An example would be instead of buying seaweed sheets at the fishstore, buy unsalted unseasoned sushi wrap - it is often the very same thing and about a quarter of the cost
what things do you guys and gals do to cut the corners in this hobby?
are there home based subsitutes for additives that you use?
I am sure a few people have ideas that would be useful for other members