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View Full Version : GVRD Boil-Water Advisory and our Reefs??


GMGQ
11-17-2006, 06:03 PM
So how is this boil-water advisory gonna affect our tanks that use auto top-offs? Mine is fed from the RO/DI.

They say to boil it because there may be bacteria in the water. (It boggles my mind that we cant even brush our teeth with tap water right now!) I assume a RO/DI unit wont really take that stuff out? So are our tanks slowly festering in bacteria??

nater3
11-17-2006, 10:15 PM
Most bacteria can't take rapid changes in salinity due to their thin cell walls so I wouldn't worry too much.
But I'd wait for someone else to chime in, I'm no expert and have no reefkeeping experience.

danny zubot
11-17-2006, 10:55 PM
Your RODI filter should remove all of the bacteria and other disolved solids that they are talking about. This period in GRVD will decrease the life of your filters, but thats what they're there for. Do you have a TDS meter? I would test your levels, and if they are still low then you should be ok.

AC33
11-17-2006, 10:58 PM
The only thing IMO that would be a problem would be the turbidity of our water, because our RO filters have a sediment filter. This may need to be changed soon if you plan to use the water coming out of your tap.

GMGQ
11-17-2006, 11:18 PM
Interesting. I thought RO/DI's were meant to take out the solids in the tap water, not organics?


Your RODI filter should remove all of the bacteria and other disolved solids that they are talking about. This period in GRVD will decrease the life of your filters, but thats what they're there for. Do you have a TDS meter? I would test your levels, and if they are still low then you should be ok.

Chad
11-17-2006, 11:35 PM
I've turned off my feed to my RO/DI cuz I don't want to ruin my filters. However, I have a 50gal drum of RO/DI already made (constantly gets refilled by the RO unit) so, I am set for a week or so. I doubt the water advisory will last long. Its already being lifted in Coquitlam and Maple Ridge.

Samw
11-18-2006, 12:39 AM
Interesting. I thought RO/DI's were meant to take out the solids in the tap water, not organics?

I guess it depends on the membrane that you bought: CTA, TFC, or High Removal.

http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=4467

Materials Removed CTA Percent(%) TFC Percent (%)
Hardness 93 - 95 93 - 97
Heavy Metals 94 - 96 95 - 98
Ammonium 85 - 90 80 - 90
Phosphate 85 - 97 95 - 98
Nitrate 50 - 70 90 - 95
Silicate 80 - 90 92 - 95
Bacteria NA >99


http://www.peteducation.com/article.cfm?cls=16&cat=1789&articleid=2890

CTA - Cellulose Tri-Acetate membranes are organic and have a slightly lower TDS removal rate of 88-94%. Because they are organic, use them only with chlorinated water (water from a municipal source) in order to keep them clean and free of damaging molds and bacteria. They do not filter out chlorine, so allow the chlorine to dissipate out of filtered water, or treat it with a chemical dechlorinator.

TFC - Thin Film Composite membranes are synthetic and remove between 94-98% of TDS. These units contain a carbon pre-filter to protect the membrane from chlorine damage. Use these membranes for water with or without chlorine.

High Removal Membranes are synthetic membranes with much higher removal rates, between 97.5-99%, and are especially adept at removing silicates. These units also contain a carbon pre-filter to protect the membrane from chlorine damage. Use these membranes for water with or without chlorine.

http://www.algone.com/reverse_osmosis.php

The two types of membranes:

Cellulose Triacetate (CTA)
This film is acceptable for treating tap water that contains chlorine/ chloramine (http://www.algone.com/water_parameters.php#chlorine). In fact CTA needs an antibacterial substance in the water, as the film is not good in removing bacteria. CTA should not be used if the water is hard (500 ppm) or has a pH above 8.5

Thin Film Composite (TFC)
This film is acceptable for hard water and can filter out bacteria. It is also well suited in holding back nitrates (http://www.algone.com/nitrates.php), phosphates (http://www.algone.com/phosphates.php), and silicates. Chlorine/ chloramine (http://www.algone.com/water_parameters.php#chlorine) on the other hand can not be tolerated. Using a TFC membrane with tap water (public water) you must pre-filter the water to eliminate chlorine/chloramine (i.e. carbon filter).