new filter or r/o sys?

Since we're in the midst of tax season, I'm going to have about $175 that Im going to put into my tank (55g, 65# live rock, sand substrate, not much livestock)

I either want to get a better filter or an r/o system.
Currently I'm using tap water, and my filter is a fairly small (but rated for a 55g tank) HOB filter. It is not the easiest thing to clean/change.
So what would do more for my tank..an r/o system or a good canister filter?

both are in my plan, but I can't decide which one should be first.

 

I would go with RO! I always purchased my saltwater from the LFS but got sick of paying $20 a week for water so I purchased an RO/DI unit. I have only had it up a couple of weeks but I can definitely tell a difference. My tap water was really bad but no tap water is really good for a reef setup. You may also want to think about a skimmer in the near future, IMHO a skimmer is the most important thing. But that is if you are wanting the keep corals, if you are just going FOWLR then maybe a filter would better suit your needs.

 

Many if not most of us have no mechanical filtration at all, only live rock, substrate like a DSB and water movement.

Get the RO/DI. If I may suggest one look at the ProPlus found here for $100 off retail and they are a 3Reef Sponsor too. Nice to support those who support our hobby.
SpectraPure Customer Appreciation SALE! 20% - 50% off

 

+1 to RODI

 

Ro/di

 

+1 on a SpectraPure 90gpd RO/DI unit, I have had mine for about 2 weeks and I love it. You can get one for $170 shipped at the above link, do it!!!!

The most important part of a SW aquarium is the water, without good water you are setting yourself up for troubles down the line.

 

Thanks for the input. I had my mind made up about the ro/di system a couple months ago, but when I cleaned my filter the other day, questioned which would make the biggest improvement. RO/DI it is.

 

Depending on the quality of your tap water a protein skimmer might be a better choice at this point ...

 

Tap water is inconsistent no matter where you are. I am a municipal water treatment plant supervisor by profession and I won't use it in my tanks. There is no reason not to use RO/DI which will be consistent each and every time if the system is maintained correctly. Water is the single largest ingredient in a reef system so why not provide the best you can.

 

I will agree AZDesertRat and add that aquarists were keeping successful marine fish aquariums long before RODI using tap water but using protein skimmers...