Strange TDS

[georgiajams]

Water from my tap is about 45-50 TDS.
Water from my RO unit is 0-1 TDS.
Water in my main Brute Trash can is 5 TDS (loosely covered, can had saltwater in it at one time, etc. so the 5 TDS seems reasonable to me).

Now, the strange part... I have an old Instant Ocean bucket that I converted to a water resevoir to feed a Kent Float valve in my sump. The bucket was drilled at the bottom and 1/4 water line was siliconed in (which runs to the float valve in the sump). This bucket has been used ONLY for fresh top off water for over a year. It sits just a few inches from the Brute trash can. No additives ever added to this bucket. TDS of the water in this bucket reads 180-210. Why?

I also have another old IO bucket that is configured the same way, although I just converted it last week. So... it is possible that this bucket has residual salt in it (although I washed it pretty good). TDS of the water in that bucket is about 50.

[goodfortune]

What are you using to transfer water from your RO/DI unit to the IO water bucket? Since your RO/DI is running 0-1 ppm, The source of TDS is somewhere between the RO/DI and the IO water bucket.

Sorry I couldn't provide more ideas; keep us posted.

- Michael

[georgiajams]

What are you using to transfer water from your RO/DI unit to the IO water bucket?

Water from the RO unit goes to the Brute trash can. When the IO bucket gets low, water is pumped from the Brute trash can into the bucket via a Maxi-Jet1200 and plastic tubing.

Now... that is one thing... I use the MJ1200 and tubing to do my water changes (and subsequently pump salt water back in the tank). That could be it... but I think it has been three weeks since I used that pump/hose for a water change. Since I evap 10g a week, that is 30g that have been through the pump/tubing/bucket. Perhaps I should drain the IO bucket, fill it up, and see if the TDS goes up. That would narrow it down to some kind of leeching problem with the bucket or silicone.

[georgiajams]

Never mind. False alarm y'all. It is measuring 5 TDS which makes more sense. Don't know how/why that happened because I retested it 3 times before. Seems to be ok now though.