RO ratio

[skydive]

I just got all replacement parts for a Coralife RO/DI and I'm having issues getting a 4:1 ratio. I got a 90gpd membrane with a matching flow restrictor and I can't get the ratio any different then 1:1? I've cut it to the length Spectrapure says and it isn't working.

 

What have I done wrong?

[AZDesertRat]

Did you contact Spectrapure?

[skydive]

Yes and they informed me of a possible 'hidden' flow restrictor inside the elbow coming from the membranes waste line. It was there, removed it and I had cut the Spectrapure restrictor to short already, a replacement will hopefully be here this week because I bought all the distilled water the grocery store had.

 

I didn't know the flow restrictor is a very important piece, didn't even know of its existence until reading the Spectrapure site. Coralife doesn't mention it at all.

[AZDesertRat]

Unfortunately most vendors don't pay enough attention to the restrictor and it is very important. Most use a fixed type restrictor that is non adjustable and we all know everyones water pressure and temperature are different, just as their TDS is. You want to be able to dial the waste ratio in so you are either not wasting too much water, thus reducing the good GPD and raising water and sewer bills, or not wasting enough and fouling the membrane leading to higher operating costs and lower quality water. As you see it only takes a few minutes to get one trimmed to fit (that is if your hadn't had the one hidden in the elbow anyway!) and it will pay off in the long run.

[skydive]

Yeah it was really easy and less time required then I had imagined.

 

I emailed them a second time with the results of 250ml/min and a ratio of 3.7 and thought I had cut it too much so I pretty much destroyed it trying to take the rest of the hose off and putting a longer piece on it. Didn't work at all. I got a response to the email today saying that I didn't cut enough off ::facepalm::

The new one will be here Wednesday though

 

Another question, since I have to change out the sediment and carbon every six months what would be a good combination to get next time? I have a 4 stage with a .5 micron sediment and a .5 carbon. If I went with bulkreefsupply filters what would you suggest I get? Shipping from Spectrapure would cost too much for two filters.

[AZDesertRat]

The only way to get the maximum life out of a RO membrane is by protecting it with the best filters you can find. I use the 0.2 micron Zetasorb prefilter myself and find it outlasts the 0.5 at least double. It has a pleated surface so gives you 10x the surface area for filtration. Lower pressure drop, better filtration and longer life are hard to beat. The better prefilter allows you to stretch out the filte rreplacements since it does a better job of protecting the carbon block so it can do its intended job of removing chlorine and VOCs, not trapping particulates and colloidal material which plugs its pores and shortens its life.

I can go a year on filters now but after 6 months I watch the pressure drop (10 months so far and only 1-2 psi drop since new) and use a low range chlorine test kit to make sure the carbon is still functioning.

 

Don't go any larger than 0.5 microns on the prefilter and 0.6 on the carbon block for best performance and i stick with the Spectrapure filters because believe it or not they even treat their top of the line prefilters like the 0.2 and 0.5 with a specila proprietary tretament proven to increase their perfromance. I don't know of anyone else who does this.

 

Have you looked at their Customer Appreciation sale flyer lately? Thhey have now added MaxCap FI resin in bulk which they have never offered before! The also have a piggyback kit to double production and many other things at great prices. Stock up on a few replacement filters and you would be money ahead.

 

http://www.spectrapure.com/email/customer-...eciation.html#1