I dedicated a whole morning and afternoon to deep cleaning this tank. Glass panels, lily pipes, hoses, filters, substrate and plant trimming - the whole shebang! There was quite a bit of detritus build up, I imagine from ailing leaves...
One thing that is perplexing me is the CO2 injection. I'm aware of the 1 pH drop guide to reach roughly 30ppm of CO2 and I couple this with a drop checker as a sort of hurdle tactic to ensure I'm achieving this. However, I notice that a 1 pH drop in my tank doesn't seem to be enough and produces a very dark green drop checker. I've noticed this in every high energy tank one had actually. The degassed water is around 7.8 (although I've seen it read as high as 8.0). Yet at pH 6.8 the drop checker is nowhere near the ideal lime green colour... In fact, according to my pH probe, I'm only getting a somewhat green drop checker at pH 6.1. The picture shows my drop checker at 6.2 and you can see it's only just green. I know the design and position of the drop checker can have an effect but I've also used a traditional shape drop checker just above the substrate and it produces the same results.
This is after 4 hours of quite rapid injection and the pipes and hoses have all just been cleaned. I'm wondering if I'm adding enough CO2 or too much, or too little. I'm a bit confused. Some help would be much appreciated!