Teach me some basics PLZ

[ReeferRob]

I admit, I don't know as much as I should by now. But hopefully you can help me with that!

Eleven months ago I purchase an RO/DI unit from Melevsreef.com.

What are some good ways to protect my investment in the unit?

How often should I replace the filtering media? And do you have recommendations (who,what, where) on replacement media?

Do you recommend or suggest flush kits?

I know I had more questions, but there escaping me right now..........

[Myteemouse]

I would strongly suggest a flush kit so the water sitting on your membrane for long periods of time can build up and cause it to slow down production and quality and life of the membrane.
Also a pressure gauge is your friend, you can see the pressure drop and know you need to change filters..
also I change mine (filters not membrane) every 6 months or so or when the pressure drops..
I get my replacement filters from BULK REEF SUPPLY.

[ReeferRob]

I would strongly suggest a flush kit so the water sitting on your membrane for long periods of time can build up and cause it to slow down production and quality and life of the membrane.
Also a pressure gauge is your friend, you can see the pressure drop and know you need to change filters..
also I change mine (filters not membrane) every 6 months or so or when the pressure drops..
I get my replacement filters from BULK REEF SUPPLY.

You get the pressure gauges from BRS too? Were do you install it? I am assuming after all the filters.

[Myteemouse]

I got the presure gague from "THEFILTERGUYS>BIZ..
it goes after the first three stages (if thats the size you have) and before the membrane..

[Chelle's Ocean]

Do you use BRS alot, Rob? What about itunes?
I catch the podcasts on itunes, have them downloaded right to my computer and then put some on my ipod. Here is the fish channel link:
http://www.fishnetwork.tv/fishnetwor...ican_Reef.html
These guys are great ! Russell & Gary are wonderful. The shows are informative, and they don't mind emails or phone calls with questions, comments, concerns,etc.
I know they have a spotlight on a RO unit, I just have to go through all the saved podcasts and find the right one. I will send it to you. (I like watching the videos and seeing the outcome on certain things I am going to try, especially the fragging duncans they did- haha we talked ALOT about that one!)
Anyway- you might want to watch the vid if you haven't seen them already.

[adalius]

It wouldn't hurt you to have a TDS monitor as well. They're not terribly expensive and when I had my RO/DI unit years ago I could compare water in to water out to make sure it was producing what it should be.

Also, I don't know if this applies to RO/DI but I know it does to straight RO units, when an RO unit shuts off it does have some bypassing where "foul" water seeps through the membrane since there's no movement through it. If you use it to fill your entire tank, you won't notice it since it'll be a few drops at the start. Where it becomes an issue is with auto top offs. If it's on a straight float valve setup, it will basically just be trickling a little water in until the float closes. Since it's cycling a little bit over and over and over, with the first couple drops being fouled, it can cause a noticeable increase in everything you're hoping to remove. It'll still be better than straight tap, mind you, just not the 99.9% or whatever your filter says it'll remove.

I don't *know* that this will be an issue since the DI should catch it, it might exhaust it that little bit faster, but it shouldn't be much. It's still something good to remember if you ever run a straight RO though.

[AZDesertRat]

The most important things for properly maintaining a RO or RO/DI system are regular filter changes at 6 month intervals, disinfecting the system at that time and making sure the waste ratio is at 4:1.
The pressure gauge and TDS meter suggestions are also good, they are the only way you have of telling prefilter and carbon block condition in the case of the pressure gauge, and membrane and resin conditions in the case of the TDS meter.

You change the prefilter and carbon block every 6 months like clockwork as they are there to protect the expensive RO membrane. Contrary to what some may think, they have very little to absolutely no effect on final TDS, they remove TSS or suspended solids, big stuff like particulates and sediments as well as chlorine which will melt a RO membrane. 6 months is a good interval if you use high quality replacement filters, if you use ebay quality filters it may be more often than that as many do not have the capacity for chlorine or sediments as good filters do. I buy all my replacement filters from Spectrapure and they are on sale here:http://www.spectrapure.com/email/cus...reciation.html

I use the 0.2 or 0.5 micron prefilter as it does the best job of protecting the billions of tiny pores in the 0.5 micron carbon block. I do not use two carbons as this is old old technology going back to the days when carbon was not as refined or developed as it is today. Some vendors still use high micron prefilters, 5 or 10 microns, which forces the first carbon to act as a secondary prefilter, what a waste since carbon is more expensive than a good prefilter and needs to have its pores open to work. If the pores are fouled or plugged with particulates and colloidal materials, many vendors don't even know about colloidals and the problems they cause, the carbon is worthless for adsorbing chlorine and volatiles.

Flush kits are a waste of money. As long as you maintain the proper 4:1 waste ratio you are doing the best you can for your membrane flushing. For a flush kit to be the least bit worthwhile you would need to operate your system manually, no autoshutoff valve or solenoids filling a top off container or pressure tank with RO only. You must open the flush valve each and every time you shut the unit off to eliminate the higher TDS water surrounding the membrane in order for it to be effective. If you miss a time or two its too late and the slids have begun to solidify of the membrane and will get worse with time. Flushing on start up has no value and if your system is automated like many of us who fill a top off reservoir or Brute can you never know hen the system is starting and stopping so cannot flush.

Use your money elsewhere like converting that extra empty canister you will have where the unneeded carbon used to be into a second DI which will give you value. Dual DI is a good investment and is relatively inexpensive if you already have the 10" canister, a few john guest fittings and a refillable cartridge and you are set.

Use the TDS meter on a regular basis and monitor tap water TDS, RO only TDS and final RO/DI TDS to check the condition of both your membrane and your DI resin. Many people only look at the RO/DI TDS and could be burning through DI resin quickly because of a borderline RO membrane. To give you an idea how important RO only TDS is, did you know for every 2% decrease in RO efficiency your DI resin life is cut in HALF? That is significant. Improving a RO membrane from 90% like the Dow Filmtec 100GPD up to 96-98% like the 75 GPD Dow would really pay for itself in DI resin savings. Or installing one of the Spectrapure Select membranes in that sale flyer which are guaranteed in writing to be better than 98% rejection would soon pay for itself at $40 when you can double your DI life over a 96 or 97% membrane. You really need to know how well your membrane is working as it affects your long term operating and overall cost of ownership. My Select membrane is operating at over 99.35% rejection rate and has been that since day one over 18 months ago. My DI life is tremendous even in Phoenix with a tap TDS of between 600 and 800.

[ReeferRob]

Very informative AZ, thank you very much.
That Spectrapure web site if very nice, but a bit pricey. I was gonna get the BRS pack until I compared the micron number in the sediment and carbon blocks. Now Im not sure what Im gonna do.

[adalius]

I just picked up one of these:
http://filterdirect.com/product_info...products_id=29

For the price I couldn't say no, plus it's got a 1:3 rejection rate which is even better than the typical 1:4.

[AZDesertRat]

The CSP-DI on sale is cheapre than any unit BRS has and is much better quality.

The Filters Direct units use low end filters so the membrane life and DI will suffer accordingly. The cost of ownership ends up being much more in time, about three times higher in fact according to test results.
Don't fall for the 3:1 waste ratio, ALL membranes should be flushed at 4:1 if you espect them to last. FD has some really deceiving sales pitches, for one their numbers never seem to add up. I try not to bash a product but they realy need to stik to drinking water systems or els do a lot of research and improve their systems for reef quality standards.