RO water and TDS help

Frontyking · Post by **Frontyking** » Fri Mar 24, 2006 5:49 am

Hello guys,

I'm picking up an RO unit next week that has a built in TDS adjustment with a digital display. With the RO unit comes a pocket TDS meter in order for me to be able to check the TDS range in my tanks.
Seeing as I've never used RO water before and am currently using dechlorinated tap water for my bi-weekly water changes, my question is what range should the TDS be set at for Zebras and is it safe for young fish IE 3.5cm which is what size mine are at now.
My understanding from the manufacturer that I'm buying the RO unit from (who has been breeding discus for over 20 years), is that using RO water for young zebras might kill them as it does young discus as they won't tolerate the low TDS. Can someone please verify this?
I've searched this and other forums on this topic high and low and have found varied opinions on what the TDS should be ranging from 20 TDS right up to 200 TDS and all have said their fish have bred which makes it very confusing and frustrating as I don't know which way to go.

BTW, water parameters in the zeb tank are:

Ammonia 0
Nitrite 0
Nitrate 3 ppm
GH 6
KH 5
PH 7.8
Is the GH and KH suitable for Zebras? I know the ph can be lowered once RO water is used.

Thanks in advance,

Nick.

Raul-7 · Post by **Raul-7** » Fri Mar 24, 2006 7:02 am

RO has a TDS of around 10ppm and DI around 0ppm; a good level to aim for is 175-300ppm. Don't worry TDS doesn't only measure hardness, it practically measures anything (conductivity) in your water that gives off a charge. Thus Ca++, Mg++, K+, Fe++ etc. are all taken into consideration by the TDS meter; so don't worry if it's high in your tap water.

Of course you can do this in two ways:
1) Mix with tap water; in this case I would use 75% tap : 25% RO given the fact your tap water parameters are ideal for Zebra's, IMO. More RO ratio and you're risking pH instability. Do you really need the RO unit?

Or

2) You can reconsitute it manually via Seachem Equilibrium (I highly recommend it; Ca:Mg in perfect ratios, adds K+ and Fe2+ for the plants) or Kent RO Right, etc.

I would go with tap as it's cheaper and much less of a headache. HTH!

Frontyking · Post by **Frontyking** » Sat Mar 25, 2006 9:58 am

Hi Raul and thanks for your reply,

the reason I'm tossing between staying with tap water and going for an RO unit is basically our water suppliers in Sydney add lime to our water when we get very heavy rain not to mention the fluoride, chlorine and chloramine, for instance, the last 4 or 5 days we have had heaps of rain, so as I always do, I test our tap water not as soon as I take it from the tap, but after dechlorinating it and several hours of aeration. An overnight aging water barrel that I tested today, gave a reading of the following:

Ph 8.5
Kh 7
Gh 9

These are the parameters I normally get after a day or two of rain and even if there hasn't been any rain the parameters are slightly lower IE, 1 point for each(Ph, Gh, Kh). It's not until I use Ph down on the aging water that gives me the readings that are in my tank which I stated in my initial post, so that basically is the reason that I'm leaning more toward using RO.

Anyone else care to comment as I'm really pulling my hair out on this one? I don't want to risk $3500 AUD of fish on a $400 AUD RO unit unless I know I can control Gh and Kh. As is, I have to tamper with the water that comes out of the tap so why not use pure water to begin with anyway?

Also, would anyone care to comment on whether RO water with a reading of 175-200 TDS will or will not harm young Zebras.

Thanks guys,

Nick.

jerms55555 · Post by **jerms55555** » Sun Mar 26, 2006 4:11 am

IM going through the same trouble as you are right now! Im looking at Aquafx and Spectra RO systems! Both are good but it drives you crazy! What I was told by a breeder and it has worked for me was to aim for a low TDS(Like Raul quoted).My first spawn was at 225TDS. I buy RO water right now from the LFS and it comes in at 20-30 TDS so I add a little tap water. And if your investing in $3500 in fish, i would definitly invest in a RO system!! And knowing your cities water line, I would just use KENT RO RIGHT.As far as stabilizing your PH, i would probably stay away from chemicals and just age your water for a day or two. This works for me, but everything is trial and error! Good luck!

Raul-7 · Post by **Raul-7** » Sun Mar 26, 2006 5:56 am

Hey Jeremy,

You may want consider a DI unit instead; it gives you 0ppm TDS. Not mention no waste water at all! The only problem is that it won't produce as much an RO unit, but it can always be recharged fairly easily with NaOH and HCl - that's if you're willing to do so.

I ended up getting the Kent Deion 200-R for that reason; all I have to do is change the carbon prefilter every six months and recharge the resins every time they are exhausted - you can tell by the color change. Much better than RO because that water goes in and directly comes out the other side, no need to wait for hours before getting 5 gallons of pure water.

You may want to consider it or eBay has great prices on RO units; $125 shipped for a 6-stage system and a 5 gallon drum.

Aiptasia · Post by **Aiptasia** » Sun Mar 26, 2006 7:46 pm

Hey, someone else who owns the Kent Deion 200-R.

I love mine. I had a Kent Hi-S R/O unit for years but it produces too much wastewater when you're dealing with a large number of tanks, and/or tanks with a lot of water volume. The Kent Deion 200-R was a godsend to my water bill.

Another good filter that a commercial SW aquarium guy I know here uses is the PolyBioMarine Kold Sterile filters. These filters were originally designed to filter water for dialysis systems and create very pure water, although not quite as pure as R/O or D/I systems, with zero wastewater. The thing that's most impressive on these filters is their flow rate, which is rated in gallons per minute instead of gallons per day.

I'd love to see an article that compares the water quality output between the average R/O (TFC) filter, a Cati/Ani Deion filter and the kold sterile filter systems.

Anyway, just another non-RO option to consider.

jerms55555 · Post by **jerms55555** » Mon Mar 27, 2006 12:45 am

Hey Raul,
the one I was actually looking at was the RO/DI units!

And it includes a drinking unit to switch between RO for drinking! I havent heard of the KENT Deion, I might have to look into that as well.
Can you have a look here, Raul and tell me what you would buy?
http://www.aquadirect.com/store/custome ... 284&page=1

or

http://www.aquadirect.com/store/custome ... 270&page=1
Thanks
Jeremy

Raul-7 · Post by **Raul-7** » Mon Mar 27, 2006 1:10 am

jerms55555 wrote:Hey Raul,
the one I was actually looking at was the RO/DI units! And it includes a drinking unit to switch between RO for drinking! I havent heard of the KENT Deion, I might have to look into that as well.
Can you have a look here, Raul and tell me what you would buy?
http://www.aquadirect.com/store/custome ... 284&page=1

or

http://www.aquadirect.com/store/custome ... 270&page=1
Thanks
Jeremy

Between those two I would get the Mako; they are identical - maybe some minor differences but nothing big except for the price difference.

But would you consider a better one of an eBay seller? Just look at this supplier; perfect! Even purer water than both the Mako and Spectrapure; and it includes everythin you need - just hook up and start making pure water. As for the ones you showed me, you still need some type of tub to hold the water - most people use the 32G plastic trash bins from Home Depot and then use an automatic shutoff valve to automate the filling process.

ungainly long links editted to here

OR. This is exactly the same as the Mako with all the nifty meters on it except half the price:

and here

One reason I never bought an RO unit is due to all that waste water is produces! For every 1 gallon of RO it wastes 3-5 gallons of water; jus think of all that waste and not mention the water bill (especially since LA's tap water is horrible)! But the choice is yours in the end, I'm just trying to save you some cash.

jerms55555 · Post by **jerms55555** » Mon Mar 27, 2006 1:44 am

Hey thanks alot bro!
I will have to check that ebay company out! It sounds pretty good! Is this the place you bought yours from?

JazzyKnots · Post by **JazzyKnots** » Sun Apr 30, 2006 7:17 am

What does "TDS" stand for? When you add the essential minerals back into the RO water, does the TDS come back into line? I've got just horrible water in Northern Cal and use RO from the local LFS most of the time. I've been mixing in some tap water for my little Zebs, but I was thinking to slowly cut out the tap water....

Raul-7 · Post by **Raul-7** » Sun Apr 30, 2006 7:57 am

JazzyKnots wrote:What does "TDS" stand for? When you add the essential minerals back into the RO water, does the TDS come back into line? I've got just horrible water in Northern Cal and use RO from the local LFS most of the time. I've been mixing in some tap water for my little Zebs, but I was thinking to slowly cut out the tap water....

TDS stands for 'total dissolved solids' basically it tells you the concentration of ions in your water and when you should change your water. Hard water typically has a high TDS, so does old tank water. Don't keep fish in TDS water under 100; minerals are essential for proper osomotic processes and diffusion in fish.

Post by **Barbie** » Sun Apr 30, 2006 7:18 pm

I know this is one of those lines of reasoning that people don't always agree with, but you actually make your quest to breed these fish HARDER by keeping them in softer water. For 99% of the fish out there, stability is the key and you're trying to match a comfortable range of parameters for the fish you want to keep together. Zebras just aren't discus. They'll thrive in VERY hard water. I kept them even when I lived in Kansas City with 17 degrees kH and 25 gH! I left them with my sister when I moved and she had them for years longer, until ice storm. Seriously, they just do NOT care about all the things people worry about adjusting for them. The pH would buffer up to nearly 9 from that water and my zebras were just as active and fat and sassy in it as they were in the soft water I had in Anchorage. More so, actually. I never crashed the pH and killed any in KC

.

If you have very hard water that they're already adjusted to going in, then when you start the rainy seasons, or spawning stimulation, you're giving them a drastic change in parameters, without having to take the TDS so low that you're risking a pH crash or rapid swings in pH when you do it. I honestly think that most people have problems because they try to hard to keep everything stable, rather than the other way around.

I have a friend that has water that's moderately hard, not truly soft, but high gH, just not much kH. If he doesn't buffer when he does water changes his pH will crash. His Hypancistrus of every variety known to man spawn like mad. He doesn't use RO. He just has built in fluctuations maybe?

I just know that when my tap water got soft a year and a half ago it became sheer hell to get my fish spawning regularly. I'm getting it figured out now, but mainly because I don't WANT to dump stuff into my tank and I've had to start adding more buffers to get the parameters up high enough to then drop them. Go figure

.

Barbie

JazzyKnots · Post by **JazzyKnots** » Mon May 01, 2006 6:05 am

Here in Nor Cal, my water is as hard as water gets. Ph is also high, natually about 8.4. The water is so hard, I can't get the Ph down without going to RO. So, it sounds like I should consider mixing half and half? End up with about 7.4 Ph and still pretty hard water? (I don't remember the actual measurements for hardness, but when I test - our water is generally off the top end of the scale. Had African Ciclids for many years, and they just loved it. My angelfish don't! So, mix half and half?

RO water and TDS help

RO water and TDS help

what is TDS

Re: what is TDS

I have VERY hard water