rodi replacement parts

Yes, your right; if you always have your Systems entirely sealed off from sunlight then it would be very unlikely for an algae problem to arise within your system, but not everyone has it hidden under a sink, or has the option.

Also important to note is that One should not judge when to change the prefilters of their system based on what they look like inside a prefilter. The appearance of the filters inside the prefilters is an indicator but a poor one as every prefilter that will remove unwanted chemicals and pollutants such as GAC's and CCB's are rated at an amount of gallons that can pass through them before the filter life becomes exhausted.

A key factor to the life span of the Reverse Osmosis Membrane is the regular upkeep of the Prefilters as this will greatly reduce the amount turbidity the Membrane will have to deal with.

As for the DI Resin Stages (which should be used when purifying water for Aquarium Use) they should be packed tightly. It can be hard to determine if the DI Resin needs to be changed if the resin does not have a color indicator built into it. For instance Aquasafe's DI Resin comes Emerald Green and when the D.I Resin Beads become exhausted they will turn brown or orange. The other sure way to determine if the DI Resin Beads are still active is to use a TDS Meter to measure the total PPM (Parts Per Million) of the water being produced by your system.
Another good tip for the DI Resin is to adjust the position of the beads inside the DI Resin Canister as Channels of water will form over time which means that the water passing through the DI Resin Canister will have less surface contact with the DI Resin.

I would recommend to any Aquarium Enthusiast to monitor the PPM count of the water being produced by their Reverse Osmosis System as it is very important to give your loved Aquarium Pets 0PPM or as close to 0PPM water as possible.

An affordable 7 stage R.O D.I Aquarium System is a combination of three prefilters, a reverse Osmosis Membrane Stage followed by three DI Resin Canisters is a sure way to get 0PPM consistently for your Aquatic environment.

 

Well, even if it's somewhere like in a laundry room, garage or restroom, it's not going to be exposed to a significant amount of light, as it'll be turned off 95% of the time anyways. So, unless the light is either on 100% of the time, or it's in direct sunlight (a horrible idea anyway), there's no issue, as by the time any significant buildup occurs the cartridges should be disinfected.

Then, we get into color changing DI resin, which isn't really the most accurate way to tell if your resin needs to be changed, but is used by quite a few people. Those definitely require clear housings, or they'd be pretty well useless. They don't really get changed on the same schedule as the prefilter and carbon, either, so you can't just go by the 6 month rule.

 

Housings really make little difference, most of us mount our units indoors in a climate controlled area away from direct lighting so clear is fine. I will say one advantage to opaque or white housings though is they handle "water hammer" or pressure spikes better than clear housings due to the materials they are constructed out of. Even with that I use and recomend clear housings. Vendors use white housings to cut costs not becaue they are better.

As for the word "stages", forget it exists. Just because someone has 5, 6 or 7 stages does not make it any better than 3 or 4 stages if those stages contain the proper filters. A unit with 3 little dinky horizontal DI tubes is nowhere near as effiicient as the same unit with a single vertical 20 oz cartridge if it is packed properly. Companies use the little horizontals to save money plain and simple, it has nothing to do with being better, or even as good for that matter. Horizontal filters short circuit or channel meaning the water takes the path of least resistance and trickles along the bottom so the upper resin may never get wet or used.

 

Dealing with many clients over a long period of time I have come across the frustrated individual that has tried everything once an algae culture has taken hold which occurred in much the same conditions depicted above.
I can also tell you that at least for Aquasafe, the cost is no different for clear housings as it is for the opaque housings. Its a choice made to eliminate the potential problem of algae that "could" occur if we supplied the clear style.

Aquasafe used to carry the 16oz DI Resin Canisters, but then chose to go with a 6oz canister instead due to the small canisters having less "channeling of water" and therefore more use of the resin overall, whereas with the much larger DI Canisters when channels form all the Beads that do not get contact usually get discarded when a DI Resin Change is made. So it was a decision to help the efficiency of the products offered.
Also important to consider is that there is now 18oz's over three smaller stages exposing the water to more direct contact with the resin where as the old style 16oz canister was only a large stage where the waters contact with the resin was limited to one channel, as channels will always form, its just a matter of how many and how large they are.

A good tip that can be used is to turn the DI Canister vertically forcing the water to percolate upward which will vastly help to maximize the use of the DI Resin. When the DI Resin Stages lay horizontally the DI resin will settle along the bottom if the DI Resin is not packed firmly into the Canister. This allows for the path of least resistance for the water to be along the top portion of the DI Canister leaving the resin in the bottom portion not getting the proper exposure to the water. If you make sure to pack the resin in tightly, this potential problem can be eliminated.

 

Sounds like you need to recommend your customers do an annual or 6 month disinfection to eliminate the algae problem as well as reduce the probability of bacteria and virus growth.

I have to disagree with you on the horizontal DI chambers and point out your information on the full size verticals is inaccurate. Science and testing tell us water takes the path of least resistance and in a horizontal that means along the bottom. You will have to do better than that to convince us. The vertical refillable cartridges hold 20 oz of DI resin not 16 so the vertical still contains more than your three little horizontals. Then consider a properly plumbed vertical DI fills from the bottom up so all resin is wetted and is used evenly, years of testing shows this to be fact. Maybe you had your 16 oz DI mounted horizontally?

I'm not sure what housings you use but all the higher end manufacturers charge more for the clear sumps than they do the opaque, white or blues. Maybe the Chinese do not? What brand of housings do you supply with your systems?