Phosphate in my RO/DI water

[hborch60]

I posted an earlier thread on my chronic algae problem. After some great advice, I have found the presence of phosphates in my RO/DI water. I have owned and used this filter for approx 6 months and use it to replace and top off water for a 40 gal. reef aquarium

I have not done any maintenance on my Aquamaxx WRU 4 RO/DI system. In fact, besides using it, I am unfamiliar with the system.

Does anyone know what is wrong and causing phosphates?
What maintenance should I be doing?

Any help is greatly appreciated as I have dealing with diatoms (I think) for 6 months now.

 

[roka64]

Hmmm, diatoms for 6 months seems a bit unlikely, as they burn themselves out, but not totally improbable.
Do you have a TDS meter? If so, test your plain tap and see what you get. If you have a high reading, you may have to change out your membrane and filter media (can't think of the word right now) in your RO/DI.

 

[hborch60]

roka,

Yeah, may not be diatoms, but I am hoping the phosphate is the source of my algae problem. Looks like I need to purchase a TDS meter. I think a serious drug habit would be cheaper than aquaria, but it is addictive!

What is TDS? Will it tell me everything I need to know about my RO/DI water. I mean if no TDS everything is good?

 

[roka64]

Can you get us a pic of the algea?
TDS= total dissolved solids. I'm not the expert on explaining or knowing too much about them. Hopefully Kurt, Larry, James, Allen, Neilan.....(well you get the point, lol!) or one of the other folks can chime in and give US better advice.

 

[lando]

Source water has a huge impact on the effective life on an RO/DI unit. Testing for TDS is a good starting point. However, the majority of PO4 is removed by the DI resin and DI membrane. The resin has a relatively short life compared to the membrane (depending on configuration) so I would suggest just replacing the DI resin container first. The DI membrane will tend to last longer and cost a lot more so start with the resin. Good luck!

 

[hborch60]

Algae pics

It looks like cyano to me. . . . . .

 

[panza]

heres a couple of sights on phosphate control and how it gets in your aquarium...


Phosphate Control in Saltwater Aquariums



About.com: http://www.athiel.com/lib3/phos.htm


How to Keep the Phosphate Levels of your Reef Aquarium Near Zero





how often do you do water changes

 

[hborch60]

heres a couple of sights on phosphate control and how it gets in your aquarium...


Thanks, very good articles, esp. About.com. It seems several problems have contributed to my phosphate problem

Anyways, didn't mean to run two threads so I will be posting on my original, algae issues dated 1/4/09

 

[MsBeanCtr]

I had a similar problem with high phosphates in my ro/di water until Kurt/Melosu pin-pointed it to my resin......I needed to change it. You might want to consider doing this.

If you really want to rid yourself of your phosphate problem you may also want to invest in a phosphate reactor (about $35). I have had great success with mine.

Good Luck!

 

[Kurt_Nelson]

I'm seeing my name bantered about, so I guess I should comment!... But lando and MsBeanCtr already stole my advice - replace your DI resin. If you're showing any amount of phoshpates coming out of your RO/DI unit, then the DI resin isn't doing it's job. Even if the RO membrane wasn't doing a single thing, the DI resin should at least give you pure water... for a while. Also, when DI resin is depleted it can actually leach contaminants back into the water. So in theory, you could have worse water coming out than going in.

So the easiest thing is to replace the DI resin. The phosphates should go away and your TDS readings should be 0.0ppm. If within a short time the phosphates reappear and your TDS goes up, that implies that the RO membrane isn't doing it's job and your DI resin is doing all the work - at that point you should probably replace the RO membrane.

And I agree... looks like cyano, not diatoms. Nice lookin' Open Brain, though!