NEW RO/DI question

[jaded]

My tank is well established and doing extremely well so of course I feel like I should change things :wacko

I just got my RO/DI unit up and running and have the first bucket of RO/DI ready for the tank. This is the first time I've used RO/DI water and I thought it was best to ask about the proceedure.

I assume that the best way to make the change is slowly so I plan on simply adding the RO/DI as the top off water for as long as it takes to get the TDS down to 0'ish then do a water change. This is just a theory and I'm open to any other advise thanks

P.S. I'm in the market to borrow (or buy) a TDS meter. PM if you have an extra one laying around you don't need for awhile (or forever).

[::pete::]

I dont see where a water change with RO/DI is going to hurt anything!

[Thunderkat]

Getting rid of dissolved heavy metals and silicates before they go into your tank will not hurt a thing ^_^

[brewercm]

adding the RO/DI as the top off water for as long as it takes to get the TDS down to 0'ish

Do you mean to get phosphates as close to 0'ish as possible. Once you add salt to the RO/DI water it's TDS will no longer be anywhere near 0. Maybe I'm just confused with what you meant. I'd just start using it for all top offs and water changes from now on. If you're battling a bad cyano problem then you can do a larger water change if you want.

[jaded]

I think I'm going to take slow... maybe a few 10% changes to start with

P.S. No cyano, no algea "problem" of anykind. Of course I have algae but its not enough to give my tangs anything to graze on, definately not a problem... Im only going with RO/DI becuase I know its a great idea in the long run for my new found love of SPS

[jaded]

New question... I borrowed a TDS meter from brewercm (thanks brewercm) and checked the 30 gallons of RO/DI i made last night. It tests at ~69. I made a small amount just a minute ago and it tests at 14. Can I assume that this will continue to to get closer to 0 as the filters get worked in or is this out of the ordinary?

P.S. My tap water tests at 300+

[alton]

For the first miniute or two your TDS will be high but as a couple of gallons run through your RO, your TDS should drop done to 1 or 2 before the DI unit if you have one. Thats why it's better to make 40 or 50 gallions at one time rather than 5.

[jaded]

before the DI unit

Does this mean that the total output (after the DI) I will get a higher TDS reading?

This is a 6 stage unit. I was told that the top filter actually adds things back to the water to change the taste to something humans might like better. I'm thinking I should get rid of that.

[alton]

My DI units don't last very long (200 gals.)so I put my TDS meter in front of the DI so I can monitor when my charcoal and micron membrane start to get bad. If you have the drinking water attachment or water polisher to the end of your RO unit this will add things back in. Aquariumfilters.com answers many of these questions.

[jaded]

thanks for the link... I'll check it out

[ReefOne]

My 6 stage i got from filterdirect is acting up. I've had it for 6 months and i've made probably 100 gallons tops and my tds went from 0 to now 10-14. Any idea what it could be. My reading in is around 45-560, it varies.

[alton]

Water in my TDS runs between 185 and 225. Is the 10-14 after one gallon or after 2 or more?

[ReefOne]

both, it doesnt change. It stays between 10-14

[alton]

I would say change your filters Micron and Charcoal and see if this helps. I think they go bad just sitting around? Your membrane didn't dry out for what ever reason did it?

[ReefOne]

how do I check that?

[BuckeyeHydro]

New question... I borrowed a TDS meter from brewercm (thanks brewercm) and checked the 30 gallons of RO/DI i made last night. It tests at ~69. I made a small amount just a minute ago and it tests at 14. Can I assume that this will continue to to get closer to 0 as the filters get worked in or is this out of the ordinary?

P.S. My tap water tests at 300+

Your DI water should be down in the neighborhood of 0 to 1 ppm tds. Lots of things can cause higher readings:
-a tds meter out of calibration
-a contaminated sampling vessel
-old DI resin (that may or may not have been burned out too fast by a bad RO membrane)

[BuckeyeHydro]

My DI units don't last very long (200 gals.)so I put my TDS meter in front of the DI so I can monitor when my charcoal and micron membrane start to get bad. If you have the drinking water attachment or water polisher to the end of your RO unit this will add things back in. Aquariumfilters.com answers many of these questions.

Your sediment filter and carbon block have negligible effect on the total dissolved solids. Read/record/monitor tds levels in three places:
1. tap water
2. after RO but before DI (to monitor performance of your membrane)
3. after DI (to monitor performance of your DI resin)

[BuckeyeHydro]

My 6 stage i got from filterdirect is acting up. I've had it for 6 months and i've made probably 100 gallons tops and my tds went from 0 to now 10-14. Any idea what it could be. My reading in is around 45-560, it varies.

Does that system have a GAC cartridge AFTER to DI? If so, carefully consider why you would want that stage there. It surely will not further purify DI water - it will add tds. Don't expect 0 or 1 tds out of the final stage if its a GAC cartridge.

[AlienAnchovies]

as far as ro goes does it have anything to do with the growth and overall health of ones corals?
or is it simply to stop pest algaes