Yes they are all basically the same thing. Glutaraldehyde is by the far the cheapest. I get a gallon bottle on line (its call Merticde 14 day solution) for around $20 a gallon mix it with 1-1/2 gallons of
RO water and get 2-1/2 gallons for about $27 including shipping. You have to shop around as many places sell it for up to $40. You also have to keep it in total light blocking containers like the Gllut comes in as light breaks the solution down rendering it useless. You also throw the little activator bottle away and never use it or it will kill everything. All you use it the gallon of Glut.