You have a point Armand ... and to be honest I did consider it. I originally chose the AC70 (the box says 40-70 gallons ....and I'm fairly new to this) because I already have 2 of them, one of each of my 30 gallon tanks. So this way I'm only buying one type of supplies, which helps my family fill in for me should I be gone for a bit.
Curtis got me thinking about extra filtration, which is why I have them on my 30s. and I liked the idea of just using 2 AC70s for now. Its a long narrow tank 12" x 48" so I figure on having one in each rear corner for now.
These are stepping stones for me ... as I teach my family as well. Should I need to buy the AC 110 down the road ... I'll be kicking myself as I did think of it originally. Fortunately this won't be the last tank I purchase so the AC70s will get used one way or the other down the road. But thank you for the input ... you confirm my original idea before I even posted anything here. Still new and probably should started speaking my mind earlier than I did.
By the way ... does my idea make sense of having the AC70s at opposite ends of the tank length-wise? Or should they be next to each other? ... Still knew and appreciate all the advice
They will work a treat anywhere you place them that shouldnt be really a prob.
Some months ago I got this 55 gal tank too and I asked a similar question about filtration. A poster commented I should be better if I go with an AC 110 instead of that AC70 that I said I have been thinking of purcheasing for that tank.
I didnt listen and got just the AC70, after all it was rated 40-70 gallon so "it overmached my needs".
Some months later I ended up getting the AC110, and the reason is not that AC70 wasnt working well, it always has, however as you mentioned extra filtration is always required and the AC110 gives you tha extra for a 55 gal.
I do not regret to have gotten the AC70 though. now it is servicing a turtle tank, so they have an usage one way or another.
Cheers.