Sorry to desert you uncgirl1! I have kept up with your thread. However, my tank cycle was complete and it was Sunday and I couldn't resist heading to the lfs for some fish (which is 1hr+ drive one way) and dealing with my own clear liquid issues.
First it is so hard to know what to do when you are unsure and there is so much conflicting information out there. Would you be willing to do a test to see if there is some credibility to my theory? 1st let me say, if the answer is no, no worries. I think the one way to forge ahead with all the conflicting info is to go with what your gut tells you. For me, I have exactly the opposite problem. My RO water is ph 6, GH 0 KH 2, my well water is ph 8, GH 23 KH 20. When I mix them 2:1, I have ph 8, GH 9, KH 9. After my visit to the lsf yesterday and talking about pH, I decided to add the Seachem Acidic buffer to bring my pH to 7. Despite what everybody says about fish adjusting to whatever your pH is. The fish I was bringing home were used to 7-7.2 and my water was 8. That's a big jump that can cause stress which can cause sickness/parasites. Also I want to get some Dwarf Gouramis and they prefer 6.5 to 7.5 max and are more delicate. The Seachem Acidic buffer worked great! 10g in 25 gallons based on the calculation and I'm at 7. It did drop my KH by 2 points though. But that's to be expected. That's what it does! So tomorrow I'm going to be experimenting with my own clear liquid again. But I digress with my own situation. Here is what I would like to see you test if you were willing.
First PWC, whatever you did the other day to bring the pH back up the 7 range. Second, turn your light off for 24 hours. I think your plants will be okay. Add to the water the full dose of Seachem Flourish Excel, like for a full water change. I can't remember exactly what that is at the moment, but I think it's 5ml per 10 gal. Third, test the pH as often as you can in that 24 hours and see if drops less, more or the same. Also, how often and how much are you dosing the Flourish Excel now?
This is what I'm basing my theory on. First based on Diane Walstad's book, Amazon Swords are a low light, hard water plant adapted to utilizing the bicarbonates in the water for their available carbon, (thus the hard water loving part). Second, you don't have a whole lot of bicarbonates to begin with. Third, I think your light may tend towards the higher output side and you where running it 10+ hours (I think?) a day which the Swords are really loving because they are used to operating efficiently in low light. Fourth, you do have 10 large swords in your tank.
So if I'm correct, and it's possible I'm not, if you get your pH and bicarbonates back up with a water change and turn your lights off, and supply your swords with another carbon source and a bunch of it. I'm hoping they might not use up your water bicarbonates so fast and we might not see the pH drop as quickly. But it may still drop. The carbon we add might still not be enough but with the light out that should definitely slow down photosynthesis which should decrease their demand for carbon. I think with is a great way to test the plant theory without removing the plants from the tank and disturbing the substrate and the mess that all creates. Plus that all adds additional factors we want to keep controlled in our test.
Anyway, let me know what you think and what you are willing to try. I think you might have to go with your gut on this.
On the discrepancy in your test, I have some distilled water here. Now obviously it's not the same as yours but it's Walmart Great Value brand. Both GH and KH are 0. One drop in both and it's very pale green and very pale yellow. I don't see any orange or blue. So I think your test kit may be off. My kit is new, opened about 1 month ago, and it expires in 2017. I do plan to replace my kits yearly regardless of the expiration date because chemical reagents are susceptible to atmospheric conditions. I would suggest, like a previous post suggested, taking a sample of your tank water to a lfs for testing if they use the API method and/or replacing your kit. Whichever is more feasible for you. I think the colors you are readying in your photos are accurate. One thing I have found in my own tests with GH and KH, is when you get close to the color change point, inverting the test tube one more time and giving it a few more seconds can mean the difference in a drop. Also at lower drops numbers, the color isn't as concentrated and therefore a change in the color is harder to see. It is definitely not a perfect system but it's what we've got!
I also wanted you know (I am not trying to aggravate the situation nor toot my own horn) that I have a BS in biology with a minor in chemistry. It's been a few years and I don't use my degree everyday but my independent senior project in chemistry was the ability of Duckweed to remove heavy metals from water. Although I don't have any fish keeping experience and I don't have 1,000s of post on this forum, I do have a credible science background and I do know a little about water chemistry.
Let me know what you decide to do and try. I'm very curious to know how it all turns out. BTW, I could very well be wrong and/or we may not be able to ever really know for sure one way or another given our limited scientific methods.
Also, I am now the very proud owner of 5 cherry barbs, 5 lemon tetra and 4 julii corys!! And I couldn't sleep, I was so worried about them! (Hence the 3 am post) I was up checking that they were still alive, not gasping at the surface and checking the pH. What can I say, I'm a proud new mom!!
