Hi, title says it all really.
90 litre 3 foot tank, been running for a year now, 85 x 30 x 40 cm.
Current stock 7 neon Tetra's, 4 glowlight Tetra's, 4 Golden Barbs, 8 various striped and spotted Danio's, 2 Bristlenose, 7cm & 5cm. Nothing new added in the last 4 months or so.
Jebo external filter been running for about 3 months stocked with standard media as included in the original box, was running in parrallel with my hang on back filter for 6 weeks to bed it in.
Half a dozen plastic plants, 2 plastic logs, 1 plastic rocky outcrop ornament, 1 large piece of bog wood, ~4-5 cm of stones purchased from LFS, Riverstone I think?.
Tap Ph 7.4 - 7.6 and seems consistent in this range. 25-30% water changes every ~10 days.
I know my stocking is close to the limit for this tank size, depending on which calculator method I use I'm either pretty much on the limit or have about 8cms spare, however I wouldn't have expected a drop of 7.6 to 6? This has only been occuring in the last 2 months or so PH was stable before that.
Any suggestions from the learned forum members?