wasp Posted October 1, 2005 Author Report Share Posted October 1, 2005 Done the 2 day test on the new carbons, they tested at Aqualight 0.38, and Rowa 0.29. These results are many multiples higher than the Jansens one, I'm wondering if the samples may have been contaminated somehow. I used different glass containers, should have done them one at a time, in the same container. Perhaps someone else has these carbons and could run a test also just to compare? If the levels really are this high any normal phosphate test kit would detect it. Quote Link to comment Share on other sites More sharing options...
reef Posted October 1, 2005 Report Share Posted October 1, 2005 That is high. will test some and see what i get. Maybe cheap carbon is better. Quote Link to comment Share on other sites More sharing options...
Fay Posted October 1, 2005 Report Share Posted October 1, 2005 Quote Link to comment Share on other sites More sharing options...
ZEOvitANZ Posted October 1, 2005 Report Share Posted October 1, 2005 Thats a shocking result Lucky an independant person tested it and not "reef" who sells it. Quote Link to comment Share on other sites More sharing options...
chimera Posted October 1, 2005 Report Share Posted October 1, 2005 So to summarise, so far we have: Jansens brand: 0.02 Aqualight: 0.38 Rowa: 0.29 I assume the RODI water was tested and confirmed to be 0 before adding carbon? Or did you use the same batch of RODI for all 3 tests? That does seem a large difference in the latter two, I suggest retesting all 3 with the same RODI at the same time? Do colourometers need calibrating? Quote Link to comment Share on other sites More sharing options...
wasp Posted October 2, 2005 Author Report Share Posted October 2, 2005 Yes same batch of water all tested at zero. The colorimeter is calibrated to zero each time it gets used. But I'm not a scientist & have realised I did make a procedural mistake, in that I used different containers. All were rinsed with RO and appeared spotless, but what I should have done was soak them for a few days in water & then test the water, just to be certain. So the test was not 100% scientifically accurate. If I can get another carbon sample I will first ascertain by soaking and testing that the containers could not contribute any contamination. Quote Link to comment Share on other sites More sharing options...
Brianemone Posted October 2, 2005 Report Share Posted October 2, 2005 yeah and you'd want a control (ie no carbon just water) dont be too hard on yourself Quote Link to comment Share on other sites More sharing options...
chimera Posted October 2, 2005 Report Share Posted October 2, 2005 dont take my remarks a bad way, just checking how you came to that result - then again its not rocket science good work so far, looking forward to more info as it comes to hand. i replaced 1kg of (jansens) carbon today Quote Link to comment Share on other sites More sharing options...
dogmatix Posted October 2, 2005 Report Share Posted October 2, 2005 from memory it can be bought in 20kg bags pm me if you need a price (sorry fo the late reply). Ben Quote Link to comment Share on other sites More sharing options...
chimera Posted October 10, 2005 Report Share Posted October 10, 2005 where are we at with this? any more results wasp? Quote Link to comment Share on other sites More sharing options...
wasp Posted October 10, 2005 Author Report Share Posted October 10, 2005 Nothing yet. However I'm going to be more careful with future tests, something along the lines of what you suggested. Nothing to report at this stage, however there may be an update here in the future if, or hopefully when, I test some more carbon. Quote Link to comment Share on other sites More sharing options...
wasp Posted November 4, 2005 Author Report Share Posted November 4, 2005 Reef has kindly supplied some more carbon as there was a possibility the first tests on the aqualight and rowa carbons had been contaminated. Turns out I did get it wrong, the fault was likely in rinsing the test containers but not actually soaking and testing them. So this time the procedure has been as follows. All water used has been tested and confirmed 0 phosphate. Then I soaked the testing containers for a week with water and then tested the water. First week there was a trace of phosphate in the water so this was discarded and the containers soaked another week. This time phosphate was zero after a week. The two carbon samples were rinsed twice with RODI to remove dust, and then placed in the containers with new water. Left standing for 2 days then tested. The aqualight performed extremely well, better than the Jansens carbon, with a reading of 0.01. The Rowa not so good with a reading of 0.15. As with the jansens carbon I'll do another test at day nine which will be more accurate as it's over a longer time. Quote Link to comment Share on other sites More sharing options...
reef Posted November 5, 2005 Report Share Posted November 5, 2005 Thats a shocking result Lucky an independant person tested it and not "reef" who sells it. Which part is shocking again. Quote Link to comment Share on other sites More sharing options...
chimera Posted November 6, 2005 Report Share Posted November 6, 2005 I enquired through a friend at a scientific supplies company about phosphate test kits and what they sell to labs etc, outside of the test kits and colorimeters that we use. Here is his reply... Hi, You don't ask easy questions. 0.015ppm is a very low level to measure with strips (can't do it) or comparators (really stretching the imagination) The lowest range we offer is from Hach and is a colour disc system. HAC2250-01 Range 0-1ppm (mg/L) This is one of three ranges this kit measures. Increments 0.02ppm Since you want to measure 0.15ppm this kit isn't really doing the job. Essentially any positive reading is too high. Worse still, the kit costs $960.00 Next level is the pocket colorimeter and if $960 scared you (when i enquired about iron testing ) then this certainly will. But it does read down to 0.01g/L (ppm). Costs around $1500 for the meter and the unit test costs are up there too. Basically it is a portable lab test with a digestion stage before colour development and measurement. Cheers Rik Quote Link to comment Share on other sites More sharing options...
reef Posted November 6, 2005 Report Share Posted November 6, 2005 Not Cheap, Deltec phostphate test kit is a lab grade kit which is a rebadged Merck test kit. cost only about $120 but if you go to a lab supplier and ask for a merck test kit it will cost over $300 for the same test kit. Quote Link to comment Share on other sites More sharing options...
wasp Posted November 11, 2005 Author Report Share Posted November 11, 2005 Done the 9 day test, the aqualight gave a reading of 0.13, and the rowa a reading of 0.39. When I did the 2 day tests i did wonder about the accuracy as they were different to the one I did a few weeks ago. However this 9 day test does seem to give a result consistent with the 2 day test allowing for some more leaching that we would expect. So it would seem the first test done a few weeks ago must have been contaminated. So the final 9 day results, for these samples anyway, are Jansens 0.10, Aqualight 0.13, and Rowa 0.39. At these low levels there can be some "noise" in the test results, so I'd say the Jansens and the Aqualight are probably similar. The Rowa, for this sample anyway, certainly leached more phosphate. Quote Link to comment Share on other sites More sharing options...
cracker Posted November 11, 2005 Report Share Posted November 11, 2005 im glad i use jansens! Quote Link to comment Share on other sites More sharing options...
jetskisteve Posted November 11, 2005 Report Share Posted November 11, 2005 Me too Quote Link to comment Share on other sites More sharing options...
ZEOvitANZ Posted November 14, 2005 Report Share Posted November 14, 2005 benton wrote Which part is shocking again. This bit ---Aqualight 0.13, and especially this bit ------- Rowa 0.39 This is the most shocking bit ------" benton " Brendan Quote Link to comment Share on other sites More sharing options...
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