Large RO Unit
 

I'm looking at getting a 1000 GPD AquaFX RO unit for my 700G total volume system. I plan on changing 100G of water once every two weeks plus using it for top off. I have an Aquasafe 100 GPD unit now. I'm just wondering if anyone thinks this is ridiculous overkill and if there are any disadvantages to a large RO unit like this? Thank you.

Membrane costs might be up there and hard to find. If you need a 100g every two weeks, and you have a 100GPD unit, you have a spare 13 days to watch it mix :)

You'd have to compare the rejection rates for the membranes it uses I think to weigh in and make a solid call there. I still prefer to use the Dow filmtec 75gpd because it's much more efficient than the 100gpd. My knowledge on the monster units is exactly zero however do you have a link? I did run a pair of the 75gpd membranes with one waste line feeding into the second membrane but then it burns the second membrane faster and you're feeding your resin slightly higher tds water.

Seriously so long as you're allowing yourself lots of time to make water why not stick with a basic unit?

It's this unit here: http://aquariumwaterfilters.com/shop...category_id=28

There's a good used one here locally with a new membrane for a really good price so I've been trying to decide if it's worth it or not. I just figured its always nice to have something like that on hand in case you need an emergency water change, etc.

Well, for the price, if you have money to part with, it's a pretty good deal. If the membrane is really new (I don't think it is), it might be worth it to pick up.

I was told its only 2 months old and that a certain someone got in trouble for changing it when the place was closing.

Sounds like overkill to me. Not sure how much water you'll loose in evaporation but I have a hard time imagining your water consumption will be more than 100 gallons a week including the biweekly changes. Worst case you can make that much water is two days if you only get half your rated output from the current unit. Might be better just buying another 100GPD unit to run in parallel for redundancy which will also double your output and won't effect cost long term since you'll double your filter life. Also a 200 gallon storage tank would be a good investment as well so you can simply maintain that much water on hand.

On the other hand you could potentially fill your tank in one day with that unit :)

Ah, ok then :)

Exactly! I've always preferred the Tim The Tool Man approach. lol

The 1:1 ratio of waste water is a useful feature.