Old larger skimmer vs. New smaller skimmer

I'm collecting equipments for my future 75. I'm looking for a skimmer which can handle a medium to heavy bioload. Someone offers me a good price on modded ASM G3X (possibly 2 yrs old). With that price, I can get a new skimmer rated for 100 gal to 160 gal like bubble magus, older model octopus, euro reef. What do you guys think?

 

How much do they want for the asm?

 

About $150

 

ASMs are a dated design and are a bit overrated. Probably would be ok on a 75g... but there are better out these days.

1 SWC 160 cone or cylinder
2 Vertex IN-100.
3 Bubble Magus NA7

 

If you could get it for $100-125 i'd say go for it. It would be fine for a 75g. imho

 

I'm sure ASM can handle my 75. It is dated skimmer but rated for 250 with sedra 5000. I also have a plan to upgrade to 125 in 2-3 years. If I get new smaller skimmer, I'll have to find another skimmer when I upgrade.

 

There is no way a G3 will do a 250g, nor would you want it to. About the biggest span a skimmer can do is twice the capacity. So you have a 75g, going to a 120. So get one rated to a 120, or a 150 max.

Things tend to happen slower than we want. It is best to get a skimmer rated for your tank. I like 150% at most. You should only go 2x if you know you will be going bigger in the near future. Just my opinion. Big skimmers perform like crap on tiny tanks.