Is this a good investment?

[Bry17nyc]

I need a RODI filter asap since the water evaporates fast in my tank
since I don't know alot about this I just wanted to know if this is a good investment...

http://cgi.ebay.com/100-G-Aquarium-...ltDomain_0&hash=item2a094b89d4#ht_12217wt_819

 

[Clownfish]

I was thinking about that unit or this one.

http://cgi.ebay.com/150-G-Aquarium-...279?pt=LH_DefaultDomain_0&hash=item588dd0ff07

I might buy it soon.

 

[LatinP]

Dont get one rated for 100 or 150gpd they may sound better but they're not, remember the higher the gpd the lower quality water you'll get. Anything below 75 is good but you'll want at least 75 to keep up and 75 is pretty much the staple unless you have a really big tank. Get one rated for 75gpd they'll give you much better water quality and usually come with the Dow FilmTec membrane (best you can get). Heres a good one:

http://cgi.ebay.com/Typhoon-5-Stage...521?pt=LH_DefaultDomain_0&hash=item2eb0b11b69

Don't go cheap on 3 things in this hobby... water, lighting and skimmer.

 

[Bry17nyc]

It makes sence .. Thanks

anything else I should have in mind with this filters?

 

[Imbarrie]

Actually that makes no sense.
Im not sure where you were informed about RODI filters but there is no advantage in water quality gained by a reduced output.
I have a 150 GPD Typhoon Extreme and it makes 0 TDS water all day long.

Some of the decisions that go into RODI filters should include;
The ease and cost of replacement filters.
How much money you want to spend.
Inlet water pressure, some filters require a higher inlet pressure than some residences provide. My 150 includes an inlet PSI gage.
Possibility of upgrades, with any large purchase, I would consider where you want to go in the next few years. Not where you are right now.

AWI makes great RODI filters, the 75 is a good filter, but the 150 is just as good and twice the output. They have been mentioined in MR as having good customer service. Ebay, not so much.

 

[Bry17nyc]

I wish I could know alot about all this stuff.. But all this filters skimmers lighting etc.. Are kinda complicated

I just need a decent rodi to do top offs and do W/Cs in a 90 gallon
I don't high budget so i'm hoping I won't have to spend alot on this one

 

[Imbarrie]

I have a 75 gallon with a 30 gallon sump. But I imagine I will be doubling that capacity in the next couple years so a 150 is OK.

A 75 GPD would be OK for your 90 but it would take a while to make enough water to do a 20 gallon WC.
The 150 comes with some nice addons, the built in gages and TDS meters are nice. Either way you go with this, you will need a quality handheld TDS meter to measure the quality of your output so you know when to change filters.
There is a lot of research on RODI online and the owners manuals helped me decide.

http://www.airwaterice.com/product/...RODI-with-Gauge-TDS-Alarm-Dual-TDS-Meter.html

 

[Dee12dee12]

actually that makes no sense.
Im not sure where you were informed about rodi filters but there is no advantage in water quality gained by a reduced output.
I have a 150 gpd typhoon extreme and it makes 0 tds water all day long.

Some of the decisions that go into rodi filters should include;
the ease and cost of replacement filters.
How much money you want to spend.
Inlet water pressure, some filters require a higher inlet pressure than some residences provide. My 150 includes an inlet psi gage.
Possibility of upgrades, with any large purchase, i would consider where you want to go in the next few years. Not where you are right now.

Awi makes great rodi filters, the 75 is a good filter, but the 150 is just as good and twice the output. They have been mentioined in mr as having good customer service. Ebay, not so much.

+1

 

[LatinP]

It's all about efficiency this topic has been beaten to death already just google it. Fact is the larger you go the more waste water you produce but that doesn't necessarily mean you're also making more pure water just a larger rejection rate so you're literally just throwing more water away out the drain line. Also alot of the newer 150gpd units don't even use a 150gpd membrane they just run 2 75s in series. Also know that a true 150 will never have the double output as a 75 you're not making the same pure water vs waste water ratio, all you really use is the pure water everything else goes down the drain, 2 75s in series with a 150 flow restictor might however.

 

[Clownfish]

I don't mean to hijack this thread but would a 75gpd AWI rodi stage 5 system be ok for a 37 gal tank?

 

[Imbarrie]

You would need to provide a credible source before I believe any of that.
And it's not all about efficiency. The OP is merely seeking advice on a filter.

Not all RODI filters are made the same and there is a large range in quality. Also note that output is rated under optimal conditions such as pressure, temperature and condition of the media.

 

[LatinP]

You would need to provide a credible source before I believe any of that.
And it's not all about efficiency. The OP is merely seeking advice on a filter.

Not all RODI filters are made the same and there is a large range in quality. Also note that output is rated under optimal conditions such as pressure, temperature and condition of the media.

Like I said this topic has been beaten to death but I'll Google some links for you. I know you want to justify you're purchase but you should know this...

Know that most modern RO/DI units are built nearly identically to each other, it's not about the housing it's about the filters way more than the 3-4 or 5 canisters and any bells and whistles a vendor puts on them, of course they'll want you to believe otherwise. Stuff like auto shut off valves, pressure gauges, flushing kits or pretty stickers and logos won't make your water any more or less pure. It's always been and always will be the pre-filters and the membrane that are doing the work.

Since you won't believe me until someone else says it:

1) http://www.reefsanctuary.com/forums/equipment/58993-ro-di-size-model-recommendation.html (scroll down to post #7 also pay attention to #11)

2) http://www.manhattanreefs.com/forum/general-discussion/71895-whats-best-complete-ro-di-system.html (right here on these very forums post #4)

I could Google all day long fact is it's a waste of time, I've already said this topic has been beaten to death.



EDIT: Answering Clownfish's question:

I don't mean to hijack this thread but would a 75gpd AWI rodi stage 5 system be ok for a 37 gal tank?

A 75gpd unit would be good for a 37g or a 100g tank, you might need more if you're tank is much larger than that but for a 37g a 75gpd would fit you just fine.

 

[Dee12dee12]

Like I said this topic has been beaten to death but I'll Google some links for you. I know you want to justify you're purchase but you should know this...

Know that most modern RO/DI units are built nearly identically to each other, it's not about the housing it's about the filters way more than the 3-4 or 5 canisters and any bells and whistles a vendor puts on them, of course they'll want you to believe otherwise. Stuff like auto shut off valves, pressure gauges, flushing kits or pretty stickers and logos won't make your water any more or less pure. It's always been and always will be the pre-filters and the membrane that are doing the work.

Since you won't believe me until someone else says it:

1) http://www.reefsanctuary.com/forums/equipment/58993-ro-di-size-model-recommendation.html (scroll down to post #7 also pay attention to #11)

2) http://www.manhattanreefs.com/forum/general-discussion/71895-whats-best-complete-ro-di-system.html (right here on these very forums post #4)

I could Google all day long fact is it's a waste of time, I've already said this topic has been beaten to death.



EDIT: Answering Clownfish's question:



A 75gpd unit would be good for a 37g or a 100g tank, you might need more if you're tank is much larger than that but for a 37g a 75gpd would fit you just fine.

Minus 1

 

[Dee12dee12]

LatinP I think you need to do a little more research, or your not explaining yourself properly. Do your research from articles and studies, not from a forum where people give opinions. Research those opinions and you will find your answer. I've been reading about large units that produce 1:1 ratio on pure/waste water. Go cheap and you get cheap. Also I have a 180gpd for my 210. In the winter I get about 118gpd and about 160 gpd in the summer and my TDS output is at 0.

 

[Imbarrie]

Well let me be the first to thank you for wasting your time backing up your statements.
But I agree with Deedee and will await your rebuttal.

 

[bizzarro]

I have a 150GPD and I have a 29 gallon. I'm not patient and don't have it set up for unattended or a permanent spot but still I'd rather be able to make more water than necessary and when I upgrade to a 65 gallon later on.

My TDS from the tap is mid to low 300s. I recently put in a diverter to use for drinking before the 2 DI and the reading was 6 after 1 sediment and 2 carbon blocks. NJ water is dirtier than NY.

 

[strgazr27]

My 100 GPD 4 stage right now is giving me about 90 GPD with a roughly 2:1 waste ratio. It's only logical that a larger unit will produce more waste water. It's how the process works. I was able to achieve a 1:1 ratio but it required me to preheat the supply water and up the supply pressure. I can get the same efficiency from a 75GPD unit as a 150GPD unit given the proper setup. To say that a larger unit is less efficient is really doing the OP a dis-service. Re-posting internet forum opinions as founded fact is also not doing the OP any good.

 

[strgazr27]

Let me rephrase what I just stated. A 100GPD Memberane is less efficient in that it does pass slightly higher TDS values to the DI resin. This will have an affect on how often you change out your DI resin but will not have any impact on how much water the unit produces. The bottom line is a 75GPD unit will give that and a 150GPD unit will give you that. Yes your waste production is higher but so is your useable water output.

 

[Bry17nyc]

Thanks everybody for the advice and all your information.. I'm with pen and paper taking notes lol

keep the info coming ! ;]