RO/DI and hard water question

[Urchinhead]

Ok. So I have found the other half of the source of my continuing diatom problem. Bad source water. I got a decent TDS meter finally and tested my tank water and ATO water. Tank water is at 296 ppm and the ATO water was at 314. So it looks like its time for a RO/DI unit for the home. I am leaning towards a mighty mite as I only need 10 gallons per week of water but may also go with the typhoon or the comparable unit from Marine Depot.

 

I have hard water. I am told it is a "4". When I talked to folks at water fire and ice I was told I needed a pre-filter on a typhoon in order to use RO/DI due to the water hardness or else I would produce no RO/DI water. When I talked to the folks at Marine Depot they said I didn't and just needed a 5 stage but would be replacing my filter more often. My water pressure is about 35 to 40.

 

After searching with no luck here my questions are these. Do I need to add a prefilter to the unit or not? Do I have enough water pressure to make RO/DI water or do I need a booster pump? Can I use the Mighty Mite or do I need to go to the typhoon?

 

Thank you for taking the time to help.

 

UH

 

Oh The first half of the problem for those of you playing along at home was not RTFM and overdosing reef chili by a factor of 4.

[Weetabix7]

That's pretty low water pressure and might cause a problem.

I thought you had to have water pressure of 50 for an RO/DI to operate properly.

Are you sure that number is correct?

Not sure what to tell you as far as who is correct, but I've heard pretty good stuff about the air, water, ice customer service and I've been pretty happy with my Mighty Mite from them. Given your water conditions, I suspect you would need a Typhoon instead of a Mighty Mite.

[Phixion]

UH, I'm thinking you might need a booster pump for your water. As Weetie mentioned, 35-40 is on the low side. I believe 60-70 is more preferable. I'm not sure about water hardness, but I can't imagine your's being much different as mine since we should both be getting our tap from the same source (MWD??) I've never tested my actual water hardness, but my tap is around 200-230 depending on a number of various conditions (mainly the season and MWD source between local wells or aquaduct water).

[Urchinhead]

UH, I'm thinking you might need a booster pump for your water. As Weetie mentioned, 35-40 is on the low side. I believe 60-70 is more preferable. I'm not sure about water hardness, but I can't imagine your's being much different as mine since we should both be getting our tap from the same source (MWD??) I've never tested my actual water hardness, but my tap is around 200-230 depending on a number of various conditions (mainly the season and MWD source between local wells or aquaduct water).

 

 

Thank you Weetie! And thank you Phixion!

 

What are you using for your RO/DI Phixion? We are supplied by Sunnyslope not MWD and I can get a higher pressure if I tap off of a washing machine line or hose most likely. The 35-40 was our upstairs bath and I remember it from when we had the house inspected before we bought about 6 years ago so I may be off...

[reefone]

id go with a full size rodi. the closer u tap into ur water main that comes into the house the higher the pressure will be. with lower preasure u will just produce water at a slower rate than if it was higher.

[Weetabix7]

Actually, I've heard that the amount of pressure affects how well the RO membrane functions.

But I'm also an RO/DI n00b and am just going off of what others have told me.

[dtfleming]

pressure, water temp and quality all effect the ro/di output. I have a 6-stage unit with hard water, it works and I get a tds of 0ppm. Problem with hard water is that your going to replace your filters sooner. I have already replaced the ro membrane once due to hard water. 35-40 psi is on the low end, but it will still work. I would trust air,water, ice advice, they would know more then Marinedepot.

[Mr. Fosi]

Where do you guys find out what your water pressure is?

[dtfleming]

Are u on welll or city water? Basically you need an inline gauge to tell you

[filefish949]

Where do you guys find out what your water pressure is?

 

go to home depot and get a hose bib adapter gauge for $8.00

 

the hard water is hard on your RO membrane, but with 10 gal/week it should last for years. it is best to put it after a water sofener

 

your water pressure is too low. you will need to get a booster pump IIRC they run ~ $100

 

I was very happy with buckeye field supply

[Mr. Fosi]

Yep, city water. Can they tell me an average pressure?

 

I'll check HD for the gauge. What section is it in? Garden?

[filefish949]

Yep, city water. Can they tell me an average pressure?

 

I'll check HD for the gauge. What section is it in? Garden?

 

 

i got mine in plumbing, once I setup my system, I took mine apart and installed it before the first stage and then the one that came with my unit I installed after my last sediment stage to tell when the pre filters are geting clogged. the HD model is very cool as it has a tattletale... I am lucky with78 psi presure, but the tattletale has shown over 100

[Urchinhead]

Where do you guys find out what your water pressure is?

 

For me it was the home inspector using a mark one mod zero eyeball. I am thinking I am going to either buy a unit with a pressure gage on it or go down to HD and pick one up to confirm it.

 

UH