Coralife Pure-Flo II 4 Stage RO/DI System 50 GPD

I have been using this product for 3 weeks. So far, I've made about 100 gallons of RO/DI water for my marine aquarium, and my only regret is not purchasing an DR/DI filter years ago. I just hook it up to my kitchen sink faucet. There was no need for crazy plumbing projects. I am a little bit concerned about the longevity of the filtering system. The initial batch came out at about 8 parts-per-million total-dissolved solids (ppm TDS), but I'm already up to 15 ppm. However, this is still a pretty low TDS, and I might even be contaminating it just by measuring or something, so I'm not too concerned yet. I do have a couple tips that might make your choice-of-purchase or set-up easier.1) Unless you plan on installing some kind holding tank and auto-shut off, this filter takes time. Remember, 50 gallons per day is only about 2 gallons per hour. If you don't think you have the patience for that, consider upgrading to a higher GPD.2) I read some reviews of RO filters that costumers were unhappy because the filtered water was acidic and/or made metal parts rust very quickly. This is not a flaw in the filter - this means it's working. RO/DI water has much less dissolved materials than most tap water. Without getting into the chemistry, this means that (1) when the water come to equilibration with the carbon dioxide in the air, it will be acidic, and (2) it will tend to oxidize (rust) metals that it comes in contact with.I use my filtered water to make home-made soda and ice cubes, but I think drinking the RO water straight is pretty gross - it just tastes awful to me. I've also heard it can be unhealthy, but I don't have much info on that.3) This filter works under rather high pressure, so there is a good chance that connections will leak. When you are assembling it, I recommend getting some teflon thread tape from the plumbing section of your hardware store. Wrap the tape tightly 2-3 times around the threads before fitting the connections to tighten everything up an prevent leaks.4) I had trouble installing the RO cartridge. The cartridge housing is not see-through, so I couldn't tell if I was installing it correctly or not. I could not tell if it was assembled correctly until I had it completely assembled to test it. But you should be able to tell if it is working by the amount of water it is producing; when working correctly, you should be producing clean water at only a trickle (~50 GPD). If you set up the filter and are getting a high flow from the product [blue] tube, you can probably assume the RO cartridge is not installed correctly. (Also, you can check the TDS if you have a meter.) It took me about four tries to get the RO cartridge installed correctly. The thing was, it needed to be pushed very hard into the fitting. The resistance was so high that I was afraid to break it.5) Many of the fitting on the unit come pre-assembled. A couple of connections on my unit initially leaked just a bit. You may need to unscrew them, wrap some teflon tape around the threads and reinstall. After I took the time to do that, my unit was 100% leak-free.6) The unit comes with an adapter that should allow you to use it with a standard sink, but installing the adapter takes a few minutes or more, and is kind of a hassle. Also, the adapter is a pretty cheap plastic, so it's prone to leaking and liable to get chewed up if you're not careful installing it every time. I alleviated this issue my permanently replacing the head of my sink faucet with one that I can directly screw the filter on to; this only cost about $3. I did not have to replace the whole faucet, but the very end has outside threads like a garden-hose connection. This has made connecting and disconnecting the filter much more convenient.Also, be aware that if you have a decorative sink faucet, the adapter might not work. You might have to be creative in installation. I live in an apartment, so I can't do any really involved plumbing projects; however, if I were in a house, I think it would be worth the effort to set the filter up with a holding tank and float valve, so that I there is always an available supply of filtered water.7) I also purchased TDS meter (HM Digital TDS-EZ Water Quality TDS Tester), and was glad that I did. It is very convenient to be able to test and see how your unit is working. My tap water comes out around 500 ppm. My filtered water has been coming out between 5 and 15 ppm. Since I can check the TDS any time I want, it will be much easier to figure out when my filter needs to be back-washed or replaced.

I took the advice of the other reviewers and removed all canisters, wrapped the threads with plumbers tape, and re-attached them. I have not had any problems with water leaking from the canisters. I did not have any issues with placing the RO membrane in the top canister, contrary to other reviewers' issues. The yellow tube that feeds the water in from your source, however, does not screw in, but rather has a pressure-based connector that does tend to leak when the system is first turned on. We use the device outside, so this is not a problem for us, but if you intend to use it inside, you'll want to figure out a way to fix this.Additionally, on the same yellow source tube, the attachment to the hose needed a washer inside of it to reduce/eliminate leaking from the connection. I had one on hand already. I could probably wrap the connection in plumbers tape as well, but 1) I ran out, and 2) we use the hose for other purposes, so it seems it'd be worn out pretty quick with the extended use. Again, it's outside, so a minimal drip is acceptable.Regarding the fill time, it seems really slow at first. When you first turn it on, give it a good 15-30 minutes before panicking if you don't see water coming from the blue hose. It took a few minutes for the water to completely filter through the system and start coming out. The TPS meter showed the first batch of water to be at or below 010, and subsequent batches have been under that baseline.After you start using the system, you'll find the filtered water fills up quicker. It seems to fill our gallon jugs within 10 minutes or so, and the 5 gallon jug within 80-100 minutes. Maybe it's just because we turn it on and then go do other things while it fills up, but it really doesn't seem to take very long.Overall, a very economical option for an RO/DI filter, particularly for aquatic setups. We had purchased an inside-the-house system that was going to require moderate plumbing to hook up, and decided to take it back & order this instead. We're glad we did.It's just as easy to store the "grey" water coming from the red tube in a container and reuse it for plants or whatever, as it is to set the blue one in your "filtered" container for collection, if you can't stand the thought of wasting all the water. We do the whole process relatively close to several potted plants, so we just place the red tube in a pot and let it trickle out.