TDS levels in RO water

[DA Mini reefs]

I'm form AUS [down under] Hi everyone,
Does anyone know if high TDS [total disolved solids] in stage 1&2 on a 4 stage RO/DI system [23ppm] is harmful in a reef tank? normal TDS level is 2or3 ppm with new cartrides. Had no replys from our own forum.

Thanks. :?

 

[Henry1]

I check my RO unit with a conductivity meter and replace the cartridges when the reading exit 20 micromhs.
Not sure what TDS of 23 ppm translate to in micromhs.

I am assuming water exiting your stage 1&2 have passed through the RO membrane.

 

[reefland]

Water exiting my RO membrane is typically in the 3 to 4 ppm TDS.

Measure your source water, and then measure the RO water. You should be getting something in the 95% to 98% rejection. If not replace the membrane.

 

[monkeyboy]

I get 2-3 tds after the membrane which drops to 0 after the post DI.

"Does anyone know if high TDS [total disolved solids] in stage 1&2 on a 4 stage RO/DI system [23ppm] is harmful in a reef tank?"

Are you testing water that is getting processed or the product water? If you test the water as it leaves or enters the 1st or second stages then sure, you'll have a whole crap load of tds, once it hits the membrane or DI it should be very low.

Kevin

 

[DA Mini reefs]

Monkyboy,
The TDS reading was 23ppm after stage 4 [DI]. It was tested by a company who supplies RO/DI water for drinking etc. useing a "spectrometer" I think it was,so I would say the reading would be accurate. BUT what effect does this high reading have on a reef tank??

 

[DA Mini reefs]

Hay Guys
I'd still like to know??? :?: :?: :?

 

[Alf3482]

I get on my TDS meter 7 ppm before going into the di and 0ppm out of the di. But in my case TDS PPM from Tap Is 552. If my TDS reads 20 PPM befor the DI I change out the front filters. HTH

 

[randy holmes-farley]

IMO, it is impossible to say with certainty whether 23 ppm TDS water is OK or not because it depends, of course, on what the solids are. Very likely it will be fine. If you need to use it, I'd suggest going ahead. But the water could contain substantial amounts of silica, in particular, if the source water is heavy with silica. You might want to determine why so much is getting through (it should not).

 

[DA Mini reefs]

Randy,
Thanks for your reply. I will check the silica level and PO4 also and then change if necessary. Pitty nowone in AUS was able to help.
David