Nina

It is definitely confusing me. I just checked my tank with the Aquarium co-op strips to be sure. The strips list "Hardness(GH)PPM)" and "Buffer(KH)PPM). My Hardness(GH) is around 300 and my Buffer(KH) is near 0. My PH is fairly stable at around 6.6.

So, I'm new to fishkeeping -- I started in February and cycled for a few weeks before adding 6 neon tetras (which are all doing great) to my 10 gallon tank. It has a few plants (anubias, a few stems, and some dwarf sagg that is starting to carpet) and gravel substrate (no driftwood). I attached the anubias to a small rock I found (and boiled). I think it is quartz or an agate and it didn't seem to change the water parameters for the first two months. However, in the last few weeks I've developed some weird problems: 1) I have low PH (6.3-6.6) even though my tap water is 7.0. I can't raise it above 6.6, which is frustrating because I'd like to add guppies or other fish that might need a neutral PH. 2) My tank has developed very high GH (the very purple square on the aquarium co-op test strips) even though my tap water is VERY soft (nothing registers on the test strips). I've confirmed these parameters with 3 brands of test strips, and have confirmed the PH readings with the strips and liquid test kit. Also, GH is very high while KH is low (it barely shows up on the test strips) The only things I add to the water are Seachem Prime, a variety of fish foods, Easy Green (per instructions), and a few Aquarium Co-op root tabs (when I started). I added 0.7 pounds of crushed coral to the substrate when I began and ran a small bag of it in my filter for a week several weeks ago -- still, the PH stayed at 6.6. I'll admit there are reasons for acids in there -- I let the tank get dirty for the first 1-2 months thinking it would fertilize the plants (not realizing that 4-5 small plants don't need all that fertilizer). That said, I've changed my ways and after some major (60-80%) water changes and cleaning I'm gravel-vacing now. I've always done a ton of water changes on this tank to keep the nitrates down to 20-40 (sometimes 3 or more 30% water changes a week). I'm so confused because it seems like low PH is usually associated with low hardness. My PH is low but GH has been very high for a few weeks now and KH is relatively low (barely registers on the test strips). What could be going on? How can lower the GH and raise the PH? Thanks!