wasp Posted November 5, 2007 Report Share Posted November 5, 2007 Well TheConch has been pretty longsuffering about his tank thread getting constantly side tracked. So I thought I better do the decent thing and start this one so as anything comes up people can post here to continue the Chch tap water discussion. Quote Link to comment Share on other sites More sharing options...
Fmxmatt Posted November 5, 2007 Report Share Posted November 5, 2007 Taken from CCC Website A typical average chemical (naturally occurring) analysis of Christchurch water pH 7.8 pH after aeration 8.2 g/m³ Acidity to pH 8.3 (as CO3) 1 g/m³ Total Alkalinity to pH 4.5 as HCO3 52 g/m³ Turbidity (NTU) Less than 1 Nitrate Nitrogen 1 g/m³ Sulphate 5.0 g/m³ Chloride 5.0 g/m³ Calcium 12.0 g/m³ Fluoride Less than 0.1 g/m³ Magnesium 1.5 g/m³ Potassium 1 g/m³ Sodium 6.1 g/m³ Reactive Silica (as SO2) 16.0 g/m³ Total Hardness (as CaCO3) 45 g/m³ Conductivity at 20ºC (mS/m) 10 Note: Grams per cubic meter (g/m³) is equivalent to milligrams per litre (mg/l). Now I'm not 100% sure about RO, but am I correct to believe that if RO was tested for all the above, it would return all 0 mg/l? And to get the beneficial values up, thats when the "quality" salt is mixed? I can see both beneficial and bad things on that list, kind of a 6 of one, half a dozen of the other scenario Quote Link to comment Share on other sites More sharing options...
alanmin4304 Posted November 5, 2007 Report Share Posted November 5, 2007 I could be wrong but I understand that RO acts as a micro filter and allows water to pass through but retains molecules bigger than water. If this is so then molecules smaller than water will also pass through. Quote Link to comment Share on other sites More sharing options...
tHEcONCH Posted November 5, 2007 Report Share Posted November 5, 2007 Taken from CCC Website A typical average chemical (naturally occurring) analysis of Christchurch water pH 7.8 pH after aeration 8.2 g/m³ Acidity to pH 8.3 (as CO3) 1 g/m³ Total Alkalinity to pH 4.5 as HCO3 52 g/m³ Turbidity (NTU) Less than 1 Nitrate Nitrogen 1 g/m³ Sulphate 5.0 g/m³ Chloride 5.0 g/m³ Calcium 12.0 g/m³ Fluoride Less than 0.1 g/m³ Magnesium 1.5 g/m³ Potassium 1 g/m³ Sodium 6.1 g/m³ Reactive Silica (as SO2) 16.0 g/m³ Total Hardness (as CaCO3) 45 g/m³ Conductivity at 20ºC (mS/m) 10 Note: Grams per cubic meter (g/m³) is equivalent to milligrams per litre (mg/l). Now I'm not 100% sure about RO, but am I correct to believe that if RO was tested for all the above, it would return all 0 mg/l? And to get the beneficial values up, thats when the "quality" salt is mixed? I can see both beneficial and bad things on that list, kind of a 6 of one, half a dozen of the other scenario My values are so different its not even close - obviously I don't have equipment to test all of those vales, but my PH, for example is always between 7.0 and 7.2, and total hardness of <1. Given that the City is supplied from several different sources, I suspect there might be a bit of variance. I'm supplied off one of the original deep bores, so I suspect my water is more 'pure' than a lot of the stuff delivered to the newer developments which have water pumped from different sources. Quote Link to comment Share on other sites More sharing options...
Fmxmatt Posted November 5, 2007 Report Share Posted November 5, 2007 Well I was thinking that myself Conch, when I was with freshwater tanks, my PH straight from the tap was 7 - 7.2 (I haven't checked it recently) If i've got some spare time tonight I might test MG, CA, and Hardness Quote Link to comment Share on other sites More sharing options...
alanmin4304 Posted November 5, 2007 Report Share Posted November 5, 2007 Less than 1 ppm hardness is realy low considering the water round the recharge area is probably higher than that. Quote Link to comment Share on other sites More sharing options...
reef Posted November 5, 2007 Report Share Posted November 5, 2007 Some readings might not be close but i suspect they have lab grade equipment so some readings will differ from standard test kits. Bore water has also got contaminates with are not good enough for reef tanks and they would be additional to the saltmix thus increasing the levels in the aquarium. The reason you should ideally use ro/di is that by adding top up water or using it fro saltmix you are adding additional contaminates and minerals which will build up in a closed aquarium. Most salymixes are designed to use with ro/di , but not using it then you are adding additional minerals etc. When making water changes and top ups you want to add zero contaminates/minerals Tapwater can still be used however for some of us who want the obsolute best water quality for our fish/corals it is not pure enough so we use ro/di. Quote Link to comment Share on other sites More sharing options...
wasp Posted November 5, 2007 Author Report Share Posted November 5, 2007 None of those things tested for would be an issue at the stated levels, other than possibly the chloride although that is easily dealt with just by aeration. To me, the stated unaerated pH, against the stated alkalinity, doesn't add up, although I'm no chemist. Agree with Reef, what is NOT tested for will be of more importance, for example one biggy, phosphate. Quote Link to comment Share on other sites More sharing options...
wasp Posted November 5, 2007 Author Report Share Posted November 5, 2007 The reason you should ideally use ro/di is that by adding top up water or using it fro saltmix you are adding additional contaminates and minerals which will build up in a closed aquarium. Most salymixes are designed to use with ro/di , but not using it then you are adding additional minerals etc. Just read that again, yes good point, even the levels stated may eventually cause some imbalance when you consider the compounding effect of continueing top up / evaporation. I was probably wrong to say they might not be an issue. But it will be some of the things not tested for that will be the bigger issue, when we get some total TDS readings that will reveal the potential amount of other stuff not mentioned in that test. Quote Link to comment Share on other sites More sharing options...
tHEcONCH Posted November 5, 2007 Report Share Posted November 5, 2007 None of those things tested for would be an issue at the stated levels, other than possibly the chloride although that is easily dealt with just by aeration. To me, the stated unaerated pH, against the stated alkalinity, doesn't add up, although I'm no chemist. Agree with Reef, what is NOT tested for will be of more importance, for example one biggy, phosphate. My Phosphate is 5ppm out of the tap. Quote Link to comment Share on other sites More sharing options...
reef Posted November 5, 2007 Report Share Posted November 5, 2007 My Phosphate is 5ppm out of the tap. That is very high. Quote Link to comment Share on other sites More sharing options...
tHEcONCH Posted November 5, 2007 Report Share Posted November 5, 2007 That is very high. Yep, hence the jar of Phospate remover and packet of Purigen jammed into the back of the tank! Quote Link to comment Share on other sites More sharing options...
reef Posted November 5, 2007 Report Share Posted November 5, 2007 IF it is that high then the po4 should be removed before entering the tank. That is just too high. Quote Link to comment Share on other sites More sharing options...
tHEcONCH Posted November 5, 2007 Report Share Posted November 5, 2007 The RSM tank water measures < 0.03 on the Salifert low scale, but it also explains why I don't need to fertilise the plants in my freshwater tanks Quote Link to comment Share on other sites More sharing options...
wasp Posted November 5, 2007 Author Report Share Posted November 5, 2007 My Phosphate is 5ppm out of the tap. Yikes!! That is a major issue How was that tested? A hobby kit or something more advanced? Quote Link to comment Share on other sites More sharing options...
Zhacque Posted November 5, 2007 Report Share Posted November 5, 2007 I'd agree with the quality of Chch water, I used to work for a "large non-alcoholic drink company" installing and maintaining postmix systems, and Chch water quality varies hugely depending on where your aquifer source is. ALSO older parts of town, e.g. Waltham, have old supply piping, which lowers the quality also. Quote Link to comment Share on other sites More sharing options...
wasp Posted November 5, 2007 Author Report Share Posted November 5, 2007 "large non-alcoholic drink company" Very tactful sticking to the no advertising rules! :lol: If that 5 ppm phosphate turns out to be a typical reading, IMO it will be a virtual impossibility for someone using it to run a clean tank long term unless spending a lot of money on phosphate removing resin or similar. If the tank was very lightly stocked chances would be better but it will certainly make life pretty hard. When I can I'll run a phosphate test on Auckland tap water & see how it compares. Quote Link to comment Share on other sites More sharing options...
tHEcONCH Posted November 5, 2007 Report Share Posted November 5, 2007 Very tactful sticking to the no advertising rules! :lol: If that 5 ppm phosphate turns out to be a typical reading, IMO it will be a virtual impossibility for someone using it to run a clean tank long term unless spending a lot of money on phosphate removing resin or similar. If the tank was very lightly stocked chances would be better but it will certainly make life pretty hard. When I can I'll run a phosphate test on Auckland tap water & see how it compares. Yep, its a typical reading for my tap - I've tested my water regularly over the last year or two and other than a slight variation in the PH, its always the same. My freshwater plants grow like mad, and I'm constantly having to replace the Phosphate removers in the RSM, so I guess I'm stuck with it. Maybe I should try RODI - the resins get expensive! Quote Link to comment Share on other sites More sharing options...
jolliolli Posted November 5, 2007 Report Share Posted November 5, 2007 wow 5ppm, thats a surprise, i'll test mine out of the tap tonight and let you know the results. Typically my pH was around 7 - 7.2 out of tap, might do a full test tonight and post the results. Quote Link to comment Share on other sites More sharing options...
Fmxmatt Posted November 6, 2007 Report Share Posted November 6, 2007 Mines untraceable out of the tap. It wasn't until I started stocking the tank that Phosphate started rising and hence I started using phos remover Quote Link to comment Share on other sites More sharing options...
wilson Posted November 6, 2007 Report Share Posted November 6, 2007 lets not forget that reefs are not super clean places i think that there is alot of people who try to hard to get all there readings at 0 or very close alot of people who over skim there tanks. JMO Quote Link to comment Share on other sites More sharing options...
JoeBlog Posted November 6, 2007 Report Share Posted November 6, 2007 Exactly. I do ~10% weekly water changes with tap. I currently don't run any phosphate removing media, feed VERY heavy, and have zero phosphate. If the readings were truly at 5 ppm out of the tap, I don't think this would be possible. I don't for sure but that's just my humble opinion and coincides with Wasp's. A tank can also have zero phosphate readings, but be FULL of algae as well since the algae may consume it all. However, I don't have ANY nuisance algae anywhere. I only clean the glass once a week with water changes and there are hardly any diatoms to clean. I mainly have to do it to keep the coralline under control. I've tested the tap water with Salifert P04 test kits ages ago and got zero readings as well. I've purchased an RO/DI unit, but it is still sitting in the box since I couldn't be bothered to hook it up. I bought a TDS meter to work inline with it and tested the tap water with it a while ago. I have a vague recollection of 20 or so. I presume that isn't good since people go on and on about zero, but I don't know any different and my tank seems to be chugging along fine. If I can remember, I will test with TDS again tonight. Just for clarification, those digital type TDS meters that go inline with RO/DI units don't have to be calibrated do they? If so, I didn't and the readings could be meaningless then. :oops: Quote Link to comment Share on other sites More sharing options...
JoeBlog Posted November 6, 2007 Report Share Posted November 6, 2007 ...alot of people who over skim there tanks. JMO Over skim??? What is that??? Is that possible??? :-? Quote Link to comment Share on other sites More sharing options...
tHEcONCH Posted November 6, 2007 Report Share Posted November 6, 2007 Over skim??? What is that??? Is that possible??? :-? :lol: Yea, whatcha' talk'n 'bout, Willis (Wilson)? :lol: Quote Link to comment Share on other sites More sharing options...
tHEcONCH Posted November 6, 2007 Report Share Posted November 6, 2007 STOP... HAMMERTIME! Quote Link to comment Share on other sites More sharing options...
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