RO systems

Question
hi I wondering if you could tell me what I need to know about reverse osmosis,like what size should I get for a 75 gallon aquarium and what is the regular maintence or any tips for reverse osmosis.Also I was wondering if you knew of any websites that have good information on these kinds of things.

Answer
Hello Alonson

All ro/di systemns are the same...

they have different stages...

The fist stages will be 'PRE FILTERS'  these filters protect the ro membrane... this membrane is the expensive component of the filter...

the post membrane filter is the DI resin... this will bring the tds level all the way down to zero...

so, whatever the ro membrane dont do, the di resin will..

you can actually use a di resin without any pre filters or any ro membrane and it will TRY to bring the tds to zero, but the resin will get all used up without the use of the pre filter and the membrane...


the difference in prices of the different filters you see around are for two things...

the first is the prefilter housing.. some are opaque and some are clear.. the clear are usually more espensive.

the thought is that you can see the cartrdigdes and know when to change them.. but if you just change them 1-2 times per year you are good to go, as those filters really dont cost that much

the other difference in cost is the ro membrane itself...

the factory tests every single membrane to see if they are performing as designed.. (the 98%vs95% etc)

IF they do perform at spec it is worth more then if it performs less then specified.

the specification, the 95v98%  is a function of how much water is needed to get to the purification you are wanting...

i.e. how much water is rejected to get 1 gallon of clean water...


I would suggest looking at www.bulkreefsupply.com  or www.filtersdirect.com

the biggest tip I would suggest is to get a float valve when you purchase your filter.. this way,.  when you fill up the jug of water, it will shut off when it fill the jug..


(this is not an 'auto shut off swithc')   It is a FLOAT VALVE   it looks like the thing inside a toilet tank above the flapper valve...


I know a lot of reefers who have forgotten about the water filter and it overflowed the jug and thier bathroom/kitchen floor...

a float valve will prevent that


good luck and let me know how things work out

If you want to discuss this more, you can log onto my new forum at www.thelittleocean.com and start a discussion there.. you will get some replies from other reefers also


good luck and hope to see you there


bill