question

[sjm1978]

hi i just bought a 6 stage ro/di unit the sixth stage is IN-LINE 10” GAC SIX STAGE CARBON FILTER my question is im only using this ro/di unit for my reef tank. so do i keep the GAC six stage carbon filter on is it safe for reef tank use i was told it wasent? i bought 2 bags of MIXED BED COLOR CHANGING DI RESIN REFILL and a CLEAR 10" INLINE DI HOUSING from you guys and was planing on running 2 di canisters because the water here is pretty bad. do i really need to run 2 di canisters? or should i just use the one inline di canister with your di resin and leave the GAC six stage carbon filter on the unit?

[Thefilterguys]

You do not need the sixth stage it is only for taste and oder for drinking water and of no use for reef water. If your water is really bad you are going to go right through your DI resin in horizontal housings. I'm guessing whatever you bought came with a 100 GPD membrane so you are going to only have a 90% rejection rate on your TDS. Any idea what your tap water TDS is?

Jim

[sjm1978]

my tds is 380

[Thefilterguys]

If you have a 100 GPD membrane that 380 translates into 38 after the RO membrane. That means you will get about 50 gallons or less of pure water before your resin in a horizontal housing is exhausted. The best thing you can do is go to a 75 GPD Filmtec membrane with a 98% rejection rate and get that RO TDS down to about 8-9. .

Jim

[sjm1978]

the membrane i have is a TFC 100 GPD RO Membrane. so if i buy the 75gpd membrane ill get tds 8-9 how can i get 0 tds? what do i need? do i have to have 0 tds? i only have softies no sps or lps i have been using ro only from my lfs but now i bought a ro/di unit what if i buy the $36.00 THE TIDE SINGLE DI SYSTEM would that make a differance or do i need the 75gpd membrane?

[Thefilterguys]

The 75 GPD membrane is the key to the whole thing and you also need the 75 GPD flow restrictor. I would'nt add the tide DI without the new membrane. It has three times the resin capacity of the horizontal but you need to get that TDS down.

Jim

[sjm1978]

ok i got another question im only gonna be making about 5 gallons of water every week. can the systems water supply be shut off and not hurt anything? i only have a 24g aquapod so i only need top off water and 2 gallons every saturday for water changes.

[Thefilterguys]

I have always run my RO/DI manually just don't drain it between uses. I ran nanos for over a year when I started and only made water once weekly with no problems.

Jim