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RO system


Apr 1, 2007
I am going to take the jump and stop those heavy hauls of RO water from the local fish store and set up a RO system near my fish tanks in my house. I have been searching around the internet looking at all different types and brands of RO systems and I was wondering if you guys and gals could point me towards stuff that has worked for you in the past or currently. I am leaning towards BRS 4 Stage Value RO/DI System - 75GPD (4 Stage Value 75GPD RO/DI System) and I want to know if you have had this set up or prefer another one.
I used eBay years ago and still use the same system (there is not much to break) Most use the same standardized components and I don't believe any branding makes much difference. You do want to record your GPD somewhere (like with a marker on your RO filter or back plate) so that you order the correct RO replacement cartridge.

I would recommend getting clear canister(s) for the particulate filter(s) as you can see it/them getting dirty (where you use carbon, transparency does not matter but it won't hurt and give flexibility if you want to change one to a particulate filter later) and would recommend using a clear canister style for the DI resin. Mine came with a clear cylindrical top placed unit but was rather small and difficult to fill so I replaced it with an additional, larger wall mounted canister style. I also HIGHLY recommend getting color coded tubing.

For extras, I recommend an inline TDS meter. Mine is connected to allow me to look at the incoming as well as the RO (ie before after the DI filtration). This is a good way to monitor when you need to replace the RO membrane.

I also have a 2 gallon holding tank that I recommend. I use a 20 gallon plastic storage container (flat sides are better than rounded) with a float valve for most of the water but I like the extra 2 gallons that are NOT DI. My system is setup to tap from the tank first, routing through the DI filter when it fills the holding bucket. I also have a faucet on the sink that uses the 2 gallon tank but does not route though the DI filter. I believe DI water has now been approved for drinking but it was not when I set the system up.

For spare parts, I recommend ordering a spare RO membrane, several tubing connectors, at least one spare shut off valve (added one to the exit point and it should come with one for the input side) and a spare flush valve (all but the membrane are very cheap and ordering with the unit will avoid shipping that would cost more than the parts).

You will need to have the unit near a sink/drain as the waste produced is about 4 times the water ( noticed that some of the units are now claiming a 2:1 waste ratio but that is still a lot of water) that it actually makes. I have mine in the garage with the waste tube sitting in the sink. I could have easily plumbed it to the drain but every so often it will run continuously and I need to back flush it, turn off the water for a day (using the unit's valve, not the main water supply) and then turn open the valve. If I could not see the waste water flowing into the sink, I would not be aware of the problem.

Here is a picture I labeled years ago (before replacing the DI filter) for someone who was trying to remember how to set up a system that had languished in the basement. I am not sure it is overly helpful :roll:
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Great info D. Just to add to this I would suggest an inline TDS meter. Its nice to see if your system is working and if your GFO is spent. Because I do high end SPS corals I wont let my system get over 1PPM TDS but if its just for an octo tank I would not have an issue at 3-4 TDS. Because of this I run a crazy 9 stage unit with 2 membranes and 2 GFO units. I can make 300g per day which is over kill for most. I used to run 8 tanks at a time and tap water was very expensive so my system runs 50% waist which is much better then normal systems.
Like D I used to run an Ebay system and it served me very well for many years. I don't think any brand is better then the other. A lot of members in my reef club use the BRS system and like it very well. Just a little pricy for what you get. Also its important that you have good water pressure. In my last house I only had about 40psi and the RO did not work very well. If you have this issue you might need a booster pump.
LOL, Good point. I HAVE an inline TDS meter on this system (needs a new battery ATM) but the pictures were taken several years ago for someone who had disassembled theirs and forgot how to put it back together.
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