TDS of 1

[Klyph]

Hello all, my RODI setup is reading a TDS of 1. I’m going to order new filters, but really need to do a water change now. Is a TDS of 1 ok to use?

 

[homer1475]

Depends on what that 1 is. Could be copper, could be arsenic, who knows.

I personally do not use anything above 0.

I have in an emergency(filters crapped out and didn't have replacements, but needed water in a hurry), have used TDS of 1, but my water is rather clean to start with at 24TDS.

 

[SPR1968]

I don’t change by RODI media until it gets to around 3-4, and I’ve never had any issues if that helps.

Ideally zero is the best of course, but sometimes, well, its not suitable to change it at a particular time so it gets left a while

 

[Gtinnel]

I usually don't replace di until my output water gets to 2. So it's best not to use it but I would/and do use water that has 1 ppm tds regularly without issue. YMMV.

 

[ihavecrabs]

Keep in mind, if your TDS is 1, it doesn't mean you need to order all new filters. You may just need to replace the DI resin. Sediment and carbon is cheap and you can replace those more often, but if your ro menbrane is still effective/efficient (96% rejection or higher) you might not need to replace it.

 

[Reef.]

With rodi resin filters, the way they work means most of that 1 TDS is going to be made up of the same substance, be it silicates, PO4 etc, so you could be adding 1ppm PO4 to your tank in one go. Or silicates etc who knows what it is.

Do you really need to do a water change now? Depending on the size, you could use distilled water from Walmart etc chances are it’ll be fine but I would prefer to wait if possible.

 

[Operator Wrasse]

If this is a real emergency, 1 TDS will not nuke your tank faster than whatever else is happening. If it's regular maintenance, skip the water change until next week. If a nem got caught in your powerhead, use the 1 TDS water.

 

[Reef.]

Keep in mind, if your TDS is 1, it doesn't mean you need to order all new filters. You may just need to replace the DI resin. Sediment and carbon is cheap and you can replace those more often, but if your ro menbrane is still effective/efficient (96% rejection or higher) you might not need to replace it.

true, good idea to have the TDS meter before the resin, so you know what TDS is going into the resin, if you have 2 probes the other is best at the end to measure the rodi TDS, most info I’ve seen suggests having the probes at the start and end, knowing what TDS is in the tap water is not going to change anything and is unlikely to change anyway.