Crystal clear water is easily achieved - there's no rocket science involved in doing that - you just have to work at it just a little bit:
- Do a large wc at least once a week (say 50%), vac substrate well with each wc, and wipe the inside glass walls down with paper towelling.
- Use a bag of Seachem Purigen in your filter - change it up & re-charge it about every 3 weeks or so.
- Use double-layered filter floss in your filter - and replace it with new every 2 weeks.
- Use a fine mesh pre-filter sponge on your filter intake - and, this is important - take it off & rinse/wring it out real well every 3 days (takes but a minute).
- Using a UV sterilizer also helps out a lot too, but not essential.
And if you're so inclined, put an AquaClear 70 filter on your tank.
Presto - crystal clear water 100% of the time.
Have a peek at my planted discus tank - running for about 3 years now - water is as clear as this all the time.