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About RandalB

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  • Birthday 04/16/1969

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    Reefs, Discus, Water treatment equipment
  1. It can have higher mineral content. Depends on your Hot Water heater. It is going through an RO unit though....RO units reject Heavy metals like copper very well. Some of your pipes are more than likely Copper as are the valves and fittings your faucets are made of. That's probably why you are using an RO unit in the first place. Minneapolis 'eh? I was just up there in Feb giving a talk to the Minneapolis Aquarium Society on RO units and Water Chemistry. Great group of people and I had a good time checking out people's fish rooms and the local Pet shops. You guys are pretty serious about your fish up there from what I saw.... RandalB
  2. I hope you didn't pay list for that unit.. Seriously though, You can increase the life of your membrane by flushing the unit regularly. You don't need to purchase a Flush kit (They do make it easier though) all you have to do is remove the flow restrictor and let the unit run for 15-30 seconds. The flow restrictor will either be a tube with fittings on either end on the waste line or a small piece of plastic that looks like a doughnut in the waste line fitting of the membrane housing. Turn the feed water off, remove the restrictor, turn the water on for 15-30 and put the restrictor back. Flushed membrane. Do this procedure 1x per week unless you have real hard water. If you do, do it everytime you use the unit. In answer to your questions: 1) My RO membranes seem to get clogged very quickly. The prefilter part is always full of rustyness (old pipes in my shatty apartment). >> Are the membranes getting clogged or just the prefilters? Most companies that make the units use plenty of prefiltration to protect the membrane. 2) Output quickly drops to a trickle >> This sounds like a prefilter problem. If that company is using smaller prefilters, you will need to change them more frequently. Try a 5 Micron Sediment and a 1 Micron Carbon. 3) RO membranes are spendy! >> Depends on where you get them. I get them for $40.00 each (75 or 100GPD Dow Filmtec's with flowrestrictor) Two more related questions: 1. Someone told me that if you ever let the RO membrane sit idle, wet, it's ruined. They stated that you must keep it going. The filter instructions, etc said nothing about it. >> This is not completely accurate. If the membrane drys out, it is more than likely ruined. If the membrane sits in stagnant water too long, it will be subject to damage from Bacteria. As a Rule of thumb, run some water through it every 3 days or so to keep this from happening. 2. How do I test the pressure of water coming out my faucet? I'd like to be sure it's enough for my RO unit to be operating at full output >> Home Depot does sell a gauge for $7.00 that attaches to a sink as mentioned above. This will tell you. RO membranes are rated at 50-65 PSI depending on the manufacturer. They are also rated at 77F, 200PPM at pH of 8.0. If your water is colder, higher in TDS, Lower in pressure or Higher in pH, you will never get the rated GPD out of it. If you want to increase output and efficiency, your best bet is to 1) Increase the Feed Pressure. A booster pump will increase the feed pressure to 100PSI and increase the unit efficiency (More output, lower waste, lower product TDS) 2) Increase the Temp of the feed water. If your water is below 77F, add some hot water to the feed. CAUTION: The glue used in making RO membranes is Temperature sensitive as is the material they are made of. If you go above 115F the membrane will be wrecked in short order. 3) Do both 1 and 2 HTH, RandalB