Where is the TDS coming from?

[NanaReefer]

I have a 6g food grade bucket that I use for mixing my makeup water in. I use a Koralia 750 for circulation and a 100w heater.
Well something's been amiss with my tank. Brown looking stuff all over the sand bed, green film algae on the glass. Parameter are all reading great and stable.
While making new water yesterday I decided to test the makeup water before adding salt to the bucket. WTH? I got a TDS reading of 160!! No this is not the reading from the RO/DI unit. I test that always and it was/is at .0
So I dump out that water to refill it. At about 4g's full I test again and now it's reading 80 TDS. So I dump that out and completely fill it to 6gs. Test and get a reading of 1.

Is there a way to clean the bucket out between usages? What is the proper way to store it? Where are the TDS coming from?

 

[Jeramy]

Probabally residule salt left in the bucket throwing of your tds meter would be my guess

 

[NanaReefer]

Probabally residule salt left in the bucket throwing of your tds meter would be my guess

OMG I didn't even think of that!! LOL AHDAH!! Thank you