Is my RO/DI filter shot?

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jcmelski

Aquarium Advice Activist
Joined
Feb 6, 2009
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I made a batch of fresh water this morning to get ready for a PWC for my 29g bio-cube tomorrow. I tested the water with my hand held TDS meter and it blinked 999, meaning there was a bunch of crap in the water. I tested the water out of the tap and it read 147. I then took a small sample of the water directly from the RO/DI unit and it read 18. Could the container that I'm using be leaching chemicals into the water? there's a brown slime in the container also. I have no idea what it is though. The container is in the basement with no top. Would water in the RO/Di unit go bad if it isn't flowing through the unit? The DI unit looks good, i.e it isn't completely depleted. it's only changed color about 1-2 inches from the bottom. Could the "brown slime" be DI resin? Is Di resin friable? What gives? I'll buy some ready made water tomorrow after work for the PWC.
 
that really really sucks big time! I've only had it for several months. I'll change out the filters but I think I should've gotten more use out of them. Any idea what the "brown slime" could be?
 
Are you treating the RO/DI with a de-chlor?
Do you have water movement in the mixing bucket?
 
Roka64
I have a carbon filter in the RO/DI unit. I'm not using any additives after the water is made. For water movement in the 35g plastic bin I'm using a moded maxi-jet 1200 with the Ecodrive unit. I retested my RO water again. I got a 0 reading using a clean cup(plastic) and high 600's if I took the water out of the tub. For some reason the brown slime is causing my TDS meter to go high(i don't know what the slime is)or the plastic bin is leaching chemicals into the water. Either way I ordered new resin, an in-line TDS meter, and I'm getting a food safe bin for the next PWC.
 
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Make a small batch of RO/DI water into a clean container and retest with a TDS meter.
 
Do you let your filter chambers go dry between use? I read that is not good for the filter media.
 
No. My filter media is always submerged. I would like to know something, I have an ASOV installed in the tub. When it shuts the water going into the tub should it also shut the drain water?
 
Is it a special ASOV? Most of them (I thought) were really only useful if you were filling into a sealed tank. The engineering being that when the line pressure gets close to the tank pressure it shuts off.

Not sure on the water shutoff. I don't run mine into a holding tank.

Have you back flushed recently?
 
I meant the ASOV is on my RO unit, sorry for any confusion. I have a float valve in the tub but when the float valve shuts the water going into the tub water continues to come out of the drain. I haven't back flushed it. should i?
 
I mean the one on your unit too...

If you haven't in a while.. it certainly couldn't hurt but it sounds like your issue is with your container and/or keeping it clean.
 
Try calling Autoshutoff.com or Bulkreefsupply and ask them about the ASOV and how it works.
 
  • How the Automatic Shut-Off Valve Works:
  • The valve automatically shuts off production when the tank pressure reaches approximately 65% of the incoming line pressure to indicate the tank is full.
  • The ASO valve saves thousands of gallons of water. Reverse Osmosis Systems without an Automatic Shut-Off valve continually send rinse water to the drain even when the tank is full.

  • Automatic Shut-Off Valve Example Process:
  • Feed water goes through a set of three pre filters (Sediment filter, Carbon filter, Carbon filter), passes through the ASOV, and then goes to the RO membrane to produce RO water.
  • The RO water passes through the system to be stored in the water tank. When the tank fills with RO water and the tank pressure reaches 40 psi, the back pressure will reverse the ASOV diaphragm and will shut off due to the pressure differential.
  • When the RO water end pressure is greater than the Feed water pressure, it causes the piston to move downward and shut off the in and out channel.
  • When the ASOV In and Out channel shuts off, the system will not produce any RO water.
So, if you're not using it w/ a closed tank it's basically useless as there is no back pressure. I applaud you for wanting to know how your unit works, seems many have them and have not a clue
 
So my ASOV is useless unless i get a sealed tank. great. thx cpt
 
reconfigure your float to attach to the inlet side... when the float trips the source water is cut off..... :)
 
I read on RC what the brown slime was. I was using IO and RC at the time and it was the vitamins in the salt. there is a long thread about it there. I'm using TM pro now and no more problems. thanks for your help
 
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