Where are the TDS coming from?

[MizTanks]

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 and 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?

[BeakerBob]

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.


What are you mixing in your make up water? If you have any saltwater or supplements left over in the bucket (dried or wet), the addition of RO/DI water will have an elevated TDS reading.

[MizTanks]

That's exactly what it was-lol. Residue :)

[AZDesertRat]

I use seperate buckets for draining the tanks during water changes and for new saltwater.
You can rinse the buckets occasionally with a vinegar solution to cut the skum or calcium build up too.

[jimsflies]

A minor amount of salt residue shouldn't hurt anything either. It is after all salt mix and should be safe. You should verify that your specific gravity is still where it should be....but I doubt a little residue will move that salinity much.

[MizTanks]

I am using separate buckets for draining and mixing ;) I simply had a brain fart-lol

[tazzy695]

the residue from mixing salt should throw off the salinity but when you put pure RO water in the bucket it will toss off the tds reading as the old residue will change that

however if you use your tds meter on mixed saltwater it will either error out or show a very high number

[mudfish]

the residue from mixing salt should throw off the salinity but when you put pure RO water in the bucket it will toss off the tds reading as the old residue will change that

however if you use your tds meter on mixed saltwater it will either error out or show a very high number


+1 agreed :highfive3:

[AZDesertRat]

Most TDS meters read to 999 on low range and some have a high range that reads by 10's up to 9,999.
New saltwater will have a TDS somewhere above 32,000 TDS so is way above the range of the meter.
If you do mistakenly stick your TDS meter in saltwater, make sure you triple rinse it in DI or distilled water right away to keep the probes clean and accurate, once a film starts to develop it will not be accurate.

[tazzy695]

good info az I never did know what the approx tds of sw would be

if you ask me you should always rinse off your meter before and after every use this eliminates possible dust or other things that might have stuck to it while in the air

[AZDesertRat]

My method for testing with a handheld meter is :
I always use a nice clean, clear glass drinking water glass, washed by hand in very hot water so it has no soap scum, residue or dishwasher rinse aids on it.
I first draw a glass or tap water and insert the meter allowing the reading to stabilize. Record the reading and triple rinse the glass and meter in RO/DI or distilled water.
Next draw a glass of RO only water and again insert the meter allowing the reading to stabilize, record the reading and triple rinse the meter and glass with RO/DI or distilled.
Finally draw a sample or RO/DI, insert the meter, record the readings and do a final triple rinse. Put the meter away with the cap installed and place the glass upside down in a clean area so it is clean for next use.

Its amazing how much things like hard water spots or stains, dishsoap reside and dishwasher rinse aids can skew TDS readings, especially when you are at the low end of the meter range like RO only and RO/DI, even a bit of dust or salt will throw it off significantly.