He's baaaaccckkk.... Well sorta

Atticus

New member
Finally got the kinks worked out and the tank is finally being refilled and will hopefully be circulating water by this weekend. Just in time for my 30th B-day on Friday...:beer: :celeb1: :celeb3: :celeb2:

I have been struggling with an ailing RO/DI that helped spell the demise of all of my corals and fish during the move to Independence. I was unable to produce a decent amount of water here due to the extemely cold ground water and extremely hard water. I was under the impression that I had fried my RO membrane and decided to experiment with it before buying a new one. It had worked well and was around a year old in Davenport.

Long story short I now have a 75 gpd membrane on track to kick out at least 75 gpd if not more and it is doubly efficient compared to its functionality in Davenport.... I went from 15-16 TDS post membrane and around 45-50gpd in Davenport to 7-8 TDS and at least 75 gpd here in Independence, after only getting about 10gpd last week out of it....

The trick was first to find the factory information reguarding the proper functioning parameters of Filmtec membranes and then use that info to my advantage. I hooked my RO up to a hot water and cold water line. I used the hot only to clean the membrane after making sure it was not hot enough to destroy the membrane or loosen the glue on the tape used to wrap the membrane. We all use TW rated low pressure membranes the TW which I thought stood for Tap Water actually stands for Tape Wrapped... Who knew? :D

Anyway, after flushing the membrane for 15 mins I mixed in the cold which also increased pressure (only about 5psi) since I am now using 2 lines to feed the membrane. It got me over the 60 psi mark. Another bonus that increases efficiency!!! :p I checked the waste line to make sure I was running at near 77 degrees, the key temp for the 75 gpd Filmtec. I reset my flow restrictor to a ratio of about 4:1 waste to good and off we went. I could not believe the difference. The flow went from a slow drip to a steady stream of good water by doing this mod and the TDS was only at 7-8 post membrane!!! I can't wait to see how this baby runs after we install a new water softener.

Just thought I would share, since this easy and cheap mod could save you all a ton of money and time. I am kicking myself for not doing it sooner...

To do this all I did was hook up a saddle valve on a hot and cold line. I then connected the 2 with a T connector. The flow from each can be dialed in using the saddle valves.

If you don't want a semi-perminent connection like this then you can get the same effect using a garden hose Y connector inverted and 2 short hoses connected to your washing machine hook-ups.
 
oh, sorry - for me it showed a bunch of those like RC dead picture type things.

its mostly working now, i can tell they are supposed to be face.
 
Man your pressure on that side of town must be horrible, if I crank the water all the way up in my upstairs shower i can blow the skin off the back of my neck, congrats on fixing the problem, if you want to save some time on cycling i change water every 2 to 3 weeks, 30 gal might give you a good start. Just let me know J
 
do you run the hot water only to flush it, or do you mix both hot and cold all the time its running?

Sounds like something I need to try with my filmtec...it has only been giving me 25tds at best
 
What is your input TDS? You run the hot through to flush and mix temps to reach 77 degrees for your running temp.
 
around 300-350, i bought the filmtec 75gpd because i thought it would be better than my 110gpd from ebay...the 110 actually did better.
 
I have about 350 going in and 8 out... Any chance you ran the 110 in the summer and the 75 now? You would definatly produce more water with the 110, but the TDS post RO is the key. The 75gpd should have a 98% rejection rate as compared to the 110gpd with about a 90% rejection rate. The 75 should have stomped the 110 for water quality, unless it is being affected by lower temp or pressure. I read 1 degree lower than 77 degrees will take away 1.5% efficency/output... You may want to try the water temp mod I was talking about.
 
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Just as a quick update... Tank and sump filled in under 24 hours. I figured it would have been about 75-80 gallons necissary to fill it with sump volume minus live rock and old nasty water keeping the rock wet.
So now that I know it still holds water, I have cleaned it drained it, threw in a sand bed because I have never had one and was tired of looking at those bags of southdown, and we are off to the races to see if it can fill in under 24 hours again...

So, far the black bag trick to keep the sand down is working AWESOME!!! Any more tips for keeping a fresh sandbed from clouding a tank would be appreciated.

Other reason for sandbed is this is going to be a fairly low flow and lower light tank for awhile. Gotta keep things cheap and rebuild slowly...
 
<a href=showthread.php?s=&postid=11596602#post11596602 target=_blank>Originally posted</a> by glaspie69
Man your pressure on that side of town must be horrible, if I crank the water all the way up in my upstairs shower i can blow the skin off the back of my neck, congrats on fixing the problem, if you want to save some time on cycling i change water every 2 to 3 weeks, 30 gal might give you a good start. Just let me know J

I actually had about 68psi when I got up this morning, so you were right, I was still running low last night. Also, thanks for the water offer, but I am going to try to kick start the cycle with some water I have sitting here from the move. It has recycled in the last couple weeks while it was holding my live rock. Man a dead tank can really ruin that new home smell... :eek1:
 
It could very well be the low temp. I have never tested the tap temp, but I'm sure its fairly cold.

I have never tried warming it first, I never thought it would make that big of difference in quality, I figured it just slowed down production. I will have to try the heater in the bucket mod sometime and see.
 
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