skuzza Posted October 27, 2004 Report Share Posted October 27, 2004 Where and how much.Also what sort of cost to maintain. Quote Link to comment Share on other sites More sharing options...
dan_from_nz Posted October 27, 2004 Report Share Posted October 27, 2004 Don't know if you can get them second hand brand new you will be looking at $350.00 - $450.00 well worth it imo Quote Link to comment Share on other sites More sharing options...
skuzza Posted October 27, 2004 Author Report Share Posted October 27, 2004 Thanks.Any more info from everyone would be good. :-? Quote Link to comment Share on other sites More sharing options...
chimera Posted October 27, 2004 Report Share Posted October 27, 2004 A little hard to come by 2nd hand. Phone Anthony Preston Limited in Howick, Auckland. Should cost you around $450 - $550 for a 4 stage RO/DI unit. Quote Link to comment Share on other sites More sharing options...
dan_from_nz Posted October 27, 2004 Report Share Posted October 27, 2004 If you are not going to be filling containers full time with it make sure you get one that has a switch to select ro or ro/di as it is unhealthy to drink de ionixed water (that is if you want to drink it aswell) Quote Link to comment Share on other sites More sharing options...
RnB Posted October 27, 2004 Report Share Posted October 27, 2004 tradme sometimes, about $80-$110 every 2 years for a membrane maybe less and about $60 a year in DI resin if you make a LOT of water..... Peter Quote Link to comment Share on other sites More sharing options...
petplanet Posted October 27, 2004 Report Share Posted October 27, 2004 Are they really worth using? Is tap water really that bad. Quote Link to comment Share on other sites More sharing options...
chimera Posted October 27, 2004 Report Share Posted October 27, 2004 for freshwater tank, not necessarily. for saltwater tank, yes in most cases. also depends on where you live though I guess, eg: christchurch seems to have very good water from what i've read. auckland,... bah! crap! :lol: Quote Link to comment Share on other sites More sharing options...
RnB Posted October 27, 2004 Report Share Posted October 27, 2004 Is tap water really that bad. if you have tested your tap water and are happy with the levels you have found then i guess you could use it. think about collecting natural seawater.... "don't collect NSW after rain as the runoff is bad".... thats how most of our drinking water is collected, run off either in the waitakere's or even via the Waikato..... I have not yet seen a good looking AKL based tank using tapwater as makeup, tho it may be possible in other locations. Quote Link to comment Share on other sites More sharing options...
Pies Posted October 27, 2004 Report Share Posted October 27, 2004 eg: christchurch seems to have very good water from what i've read. auckland,... bah! crap! Christchurch water is mineral water and is not treated with any chemicals. However I personally don't think you should be using it un-filtered, for top-off or saltwater mix. There has to be lots of minerals etc in there that have an effect on the tank. Is tap water that bad? Yes. Pie Quote Link to comment Share on other sites More sharing options...
suphew Posted October 27, 2004 Report Share Posted October 27, 2004 Any comments on using rain water other than it being quite soft? I've used to for years with my Discus, done basic water tests on it, all clear, and checked with NIWA who say no pollutants because of winds keeping air clean (yeah for windy wellington!). Quote Link to comment Share on other sites More sharing options...
suphew Posted October 27, 2004 Report Share Posted October 27, 2004 Just as a random comment, friends in London call the 'drinking' water "7 kidney water" because thats the average number of people the tap water has passed through Quote Link to comment Share on other sites More sharing options...
skuzza Posted October 28, 2004 Author Report Share Posted October 28, 2004 Thanks for the help guys.Our tap water down here is full of phos.I will tell my partner that we realy need one for our health and the extra hot summer thats on its way.(year right) Quote Link to comment Share on other sites More sharing options...
chimera Posted October 28, 2004 Report Share Posted October 28, 2004 Arhhh, good old rotovegas. Was down their last weekend, there's so much to do in your town! I wonder if the phos has something to do with the ground Rotorua sits on (all the mud and stuff! :-?) Quote Link to comment Share on other sites More sharing options...
Warren Posted October 30, 2004 Report Share Posted October 30, 2004 The phos here in HB is pretty bad too, 6-8ppm out of the tap. No good for planted tanks unless you want green algae. No good for salt mix either as the phos strips the calcium. I've been using just RO for years now, - the only way to have an algae free planted tank. Even the seawater here can have up to 1ppm phos due to 13+ rivers emptying in Hawke Bay... Why do you use a DI after the RO for marines?. A good RO removes 99.95% of all dissolved molecules to start with. The tapwater isn't all that bad in NZ to start with, just not quite good enough for some of the more sensitive artificial environments like Marine Tanks and Planted freshwater tanks with the same lighting as a marine... Quote Link to comment Share on other sites More sharing options...
chimera Posted October 30, 2004 Report Share Posted October 30, 2004 Why do you use a DI after the RO for marines?. A good RO removes 99.95% of all dissolved molecules to start with Thats exactly why, because RO isn't 100%. With marine's (or rather reef tanks), when you're talking about anything over 0.03ppm of phosphate = bad for corals then you want to get rid of as much crap as possible. Additionally, RO by itself doesn't last long and is relatively expensive. DI (after RO) does last long (a year or more). Having pre-filters and activated carbon filters prior to the RO means even longer lasting for both RO and DI. Having pre-filter, activated carbon, RO then DI means you're covering your arse by filtering as much bad stuff as possible - even that extra 0.05% means alot in a reef tank. Quote Link to comment Share on other sites More sharing options...
Warren Posted October 31, 2004 Report Share Posted October 31, 2004 RO is the cheapest form of water purification by a long shot... Try using just DI on it's own and you'll pay megabucks for resin (or regen it every week or so). The DI only lasts so long because there is stuff all for it to do after the RO to start with. A good RO will produce about 70000L of water on one membrane and set of pre and post filters. I get over 100000L out of mine... No need for DI on fresh water tanks. Also, DI would be detrimental as it replaces whatever is in the water with sodium ions, - less than desirable in a planted tank but ok in a marine. Quote Link to comment Share on other sites More sharing options...
Pies Posted October 31, 2004 Report Share Posted October 31, 2004 Thats why the reef keepers use RO, its only there to prolong the life of the DI. Pies Quote Link to comment Share on other sites More sharing options...
chimera Posted October 31, 2004 Report Share Posted October 31, 2004 ...and pretty much what i said in my post Quote Link to comment Share on other sites More sharing options...
Warren Posted October 31, 2004 Report Share Posted October 31, 2004 Additionally, RO by itself doesn't last long and is relatively expensive. This is your original post, nothing to do with what I said... RO not only last much longer than any other type of purifier but it's also the cheapest water purifier, especially for how effective it is. It might only remove 99.5% but so does DI. Quote Link to comment Share on other sites More sharing options...
dan_from_nz Posted October 31, 2004 Report Share Posted October 31, 2004 DI is actually bad for fresh water fish it pulls nutrients out of the fish (somthing to do with the mucas layer and osmosis) and can kill them Quote Link to comment Share on other sites More sharing options...
Pies Posted October 31, 2004 Report Share Posted October 31, 2004 The RO/DI concept is just a way to ensure that you are getting as close to distilled water as possible. Because the reef tankers use evaporation to suppliment calcium hydroxide (Kalkwasser) and to avoid heat, its just a case of not wating to put anything else in except whats been taken out by evaporation. Same deal with saltmix, just add water. By water they mean water, not 'wet mineral soup'. From what I understand RO and DI work quite differently. For example an RO unit will remove sediment, parisites etc from the water, DI cannot and does not do this. RO is a mechnical filter and DI is a chemical filter. As I understand it. RO wastes a lot of water and good units are fairly expensive. The prefilters are only used to extend the life of the RO unit, which is mostly unded to extend the life of the DI media. Warren is probably right about 'why' use DI when RO is so good. I am going with the sheep on this one and doing it because its the 'norm'. It costs me about $20 a year to run the DI, so if that saves one coral or fish every 3 years its paid for itself. Pieman Quote Link to comment Share on other sites More sharing options...
dan_from_nz Posted October 31, 2004 Report Share Posted October 31, 2004 there is a thread in the chemistry forum on rc about dom and pom that from it has a link explaining ro/di in great detail and how it works relative to a reef tank (a little off the point but thought you may be interested) Quote Link to comment Share on other sites More sharing options...
Ira Posted October 31, 2004 Report Share Posted October 31, 2004 Since we're on the subject, would it matter if a DI filter is mounted horizontally instead of vertically? Just because the units won't fit in my stand vertically but WILL fit horizontally. Thought it'd be nice to actually have it in the stand instead of throwing them in a closet when I'm not using it like I am now... Quote Link to comment Share on other sites More sharing options...
Pies Posted October 31, 2004 Report Share Posted October 31, 2004 I would think that as long as the water travels the same path it wouldn't matter one bit, as long as the contact time with the water and media remains the same or similar? Pie Quote Link to comment Share on other sites More sharing options...
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