RO/DI question

[Herefishyfishy]

Filter media captures and then bacteria breaks down wastes into various chemicals until eventually becoming nitrates. Water changes rids the tank of the nitrates. In saltwater aquariums, most of the "filtration" happens with protein skimmers removing most of the waste followed by bacteria in live rock breaking the rest down to nitrates. The refugium you are setting up is full of plants that feed on the nitrates, and when you pull excess plants out, you are exporting the waste as "consumed nitrates"

BROUSE THIS SITE AND FIND MANY GREAT WRITEUPS ON HOW ALL THIS WORKS. pERHAPS WE CAN ALLOW THIS THREAD (sorry cap locks) to get back to the subject of RO/DI water purification.

 

[reedman]

If your input is 100 the you should have at very least 4 remaining if all conditions are perfect but in reality 6 to 10. Your di is removing quite abit. Since tds is an equation based on a number of parameters the conductivity even with low tds is still quite high. So in short the di is doing more than meets the eye.

Don

Don,
I would normally agree, but my DI has been on this unit for in excess of 6 years.....must be exhausted. In fact it is probably putting silicates back into the water. I plan to try it without and see what the readings are. If I see an increase in TDS or algae in the tank I can just add a new DI filter back on.

Thanks for all the info though. I completely get what you are saying and don't dissagree. Just think that with how out of date mine is I think it is doing more harm than good.

 

[DonW]

You can definatly go without but you will have residual tds from the membrane. If yours is junk then you already have that anyways so it really doesn't matter. The di is the only way to get rid of that residual. If your meter is showing 0 tds with a junk di then the meter is off and needs calibration.

Don

 

[reedman]

nope....tds is showing between 4 and 6 which is inline with what you mentioned earlier