If I were you, I would consider a canister filter and a power filter.  I have a 75 gallon tank and I have a fluval canister filter, with the Aqueon 55-75gallon power filter.  The fluval only needs once a month maintenance which is so easy and nice to use.  The aqueon, I rinse the filters in tank water when I do my weekly water change and then once a month I change out the filters or when they become clogged, sometimes they last for 6 weeks.  I have an Eheim canister also on my 55 gallon tank with an Aqueon filter too.  I have to say I like the fluval filter better.  On my 90 gallon I have both the marineland power filter and also the marineland magnum 350 canister filter.  Of all these filter systems, I personally think the Aqueon power filters are the easiest to use and perform the best keeping my water crystal clear, and the same for the fluval canister filter.   Of course it all comes down to personal preference and choice and also, expense also plays a part in it.  Get the best you can afford, you won't be sorry!

WOW!  Thanks for the detailed answers     It really helps someone like me who is still trying to gain experience.

I have an Aqueon on my 10 gal tank, and really like it.  I'm going to research your recommendations and will probably end up with both a canister and power filter.

I thought I read somewhere (not on this forum) that a canister filter can harbor bad bacteria or something like that, so I always thought they were bad.  But many of you seem to have success with them, and I will try it.

I'm willing to spend whatever it takes to have the best for my fish, without going too far overboard of course.  

This is a good question and I thought the same thing when I transfered from a 10 gallon to the bigger deeper tank. At first my sweet fish was a little disoriented but quickly began exploring his new home and the depth/greater pressure made no difference to him. I speak of my beloved Ryukin I recently lost but it was due to illness not the tank. Currently recycling the tank for my new 4 month old Ryukin Jillyfish who is in my 10 gallon and possibly getting another goldie soon too.

I am very excited for you though as I went thru the anticipation of the initial set up and then the cycling, it was almost like waiting for xmas! Sorry for going off topic there just sharing the connection to your question. Get yourself started with either filter or better would be both but get started as the cycling does take time. It is so worth it the wait. 

I am using an AquaClear on my 40 gallon tank and I love love love it! My water parameters are always perfect and the water is crystal clear! The filter media that comes with the filter is really good too (foam, carbon and biomax)
The only thing you ever need to replace is the carbon The foam and biomax just need to be rinsed every month or so.
But a lot of people do believe it is better to buy a canister filter with a tank as big as yours. I am planning on buying a canister filter when I get a bigger tank and will be definitely getting an Eheim. I cannot speak from experience but I have read dozens of reviews online and have talked to people who use them and they could not speak higher of them! A lot of people have had theirs for 15 years and it is still working as good as the day they bought it.
If you have the money you can run an aquaclear and a canister filter? You can't have to much filtration (as long as the flow in the tank is not too strong for the fishies )
edit: If you do decide to go for just an aquaclear filter then make sure you get the 110 version

My fish weren't affected at all by the water pressure, even if this tank is almost 10 times bigger than what they originally lived in!
As long as the water quality is good, they'll be fine

Either way, my tank is slightly bigger than yours, so I've got an external filter rated for a tank twice the size, while I also have an internal power filter at the same time. It works great During water changes I usually only clean out the internal filter, and I wash the filter media in the external one about once a month or a bit more seldom. None of them are particularly dirty, so that should be just enough in my tank

That's a combo that's sure to work! I usually leave the external filter on while I'm changing the water, just because it's a slight agony trying to get it going again.

canister filter are better because of water movement. u can put the inlet on one side of the tank and the output on the other for good movement like a sump. the bad thing about hob filters is the intake is right below the output so when some of the clean water get put out it goes right back into the inlet and get cleaned before it gets dirty and the water on the far side of the tank rarely ever get clean cause it stay still so u will have clean water in the middle and dirty on the sides

if u look at your water level on the both sides of the tank and see small waves that mean for the most part this is not a problem. if u dont see movement the u should get put an air stone on the sides to move the water or better yet get a power head to push the water

if u do get a hob get a marineland emperor biowheel. when the water leaves the out put it get sent outward not downward and makes lots of movement I have a marineland  400 on my 55 gallon tank that is 4 feet long and it does the job for my saltwater tank. only cost me 35 $ used ha

That's good advice Creamkiller, but for Goldfish, which are extremely messy, the best of both worlds is better.
In that I mean a canister filter backed by a power filter (hob), will be the most efficient way of controling waste in the larger aquariums like a 75g or more.
I know everyone LOVES the Emperor 400, but I personally feel the Aqueon is a much better product and provides the same effect as the Emperor only better.  I have the maraineland canister and hob on my 90 gallon (only freshwater tropicals in that) and my water is never as crystal clear as the Fluval canister and Aqueon hob filter combined. (75 gallon and 12 big goldfish in there)
If I had the money, I would switch all my tanks to that.

Thanks Creamkiller for describing the water movement. Something so simple, but if you don't think about it, could cause problems.  All I need is a little nudge like that and I'm off reading and learning more about it.
It's great to hear everyone's opinion.

Creamkiller: Goldfish are messy in the way that they are producing a lot of waste. Both ammonia and excrement. Not how much food they leave around.

April: The air stones don't produce oxygen, but cause surface movement as the bubbles hit the surface. So putting the air stone in front of the filter doesn't help that much

@ Nossie: April didn't say that the airstone PRODUCES O2. It is simply that the air going through it just contains it.

I recently installed the canister filter and it has a spraybar going across the whole back of the tank. My airstone is 50cm long too. I only can put it basically underneath the spraybar and there is an incredible watermovement.

Also if the spraybar is NOT submerged, the water coming out of it gets O2 of the air. In this way one can provide good water saturated with O2.

I am having the same questions here.  I have the Emperor as this use to be a saltwater tank.  I have a 75 gallon in wall tank.  I just bought new filters and wheels for this thing and I hope I didn't waste my money.   
This tank is 4ft long, 17"high, and looks like around 18"deep, in the wall so hard to measure.  I checked out those canister filters after reading this post and they are quite expensive indeed.  Is there something special I need to put in the plastic things that go in the system I have?  lol I sound like a tard I know, can't remember what they are called.  They come apart and have little shelf looking things in them.  Hope you know what I am talking about.  Not sure what goes in there as a freshwater system. 

Also, should I be using special filters for this?  I bought the E filters that go with the system.  Anything special I should be doing when cleaning them out? 

Not sure what creamkiller is talking about doing with the pot scrubbers, where do you put these and what kind do you use? 

So many questions I know. 

Is the Fluval canister noisy? Is it louder than the other canisters mentioned?

Sorry Minde I was so confusing in that post.  Ok, I have the HOB Emperor system, had it already from when I bought the tank.  I bought the E filters for it and just rinsed them out and put them in the system.  There are these plastic tray type things that go with the Emperor and I didn't do anything with them yet, didn't know what to put in them, they are the ones I said come apart and have the little shelves in them.  To keep it good and clean when I get this thing cycled and put my goldfish in what do I need to use in the Emperor system?  I am completely lost now. lol  You said scrubbies can be put in the canisters or in the back of the system.  What kind of scrubbies are you talking about?  By canisters do you mean the trays I said that I didn't use yet?  Wow I need to post a picture so everyone knows what I am talking about but I don't have one atm.  I just want to get the best filtration I can for now and maybe upgrade when I can afford it, its cost alot to reset everything up so far.  I don't know the terms for everything yet either which doesn't help I'm sure.  

Bel,
That Emperor HOB filter won't be enough for a 75 gallon tank with goldfish in it.
If you want to keep healthy fancy goldies then you need to look into getting another filter system besides the HOB one.
I suggest a canister filter too.
Creamkiller is talking about the plastic scrubbies you use to scub teflon pots with, that you can get at the dollar store.
You can shove them in the HOB filter or put them in the canisters but I have not used these.
As far asthe tray things in your HOB filter, you can fil them with whatever you want to, carbon, carbon, zeolite mix, tiny ceramic media, etc.  I currently have carbon/zeolite mix in mine.  Make sure to rinse them well after filling, before putting them in the filter.
They go in the slot closest to the aquarium and then the E filter behind that blue facing the wall or back of filter.

Thanks for your quick replies, I had your answers by the time I got to the store.    

I've been buying things from Petsmart, as they have a sale going until Jan 30, which is great because that means I don't have to buy everything all in one trip.  Gives me time to research things before buying.