How Can I Change My Water And Clean My Gravel?

[cooledwhip]

Hey all I have some questions about cleaning my tank. I have a heavily planted tank with some S repens and lots of other plants. I change my water and I just can't vacuum my substrate. (seachem flourite).
 
I can see all the specs of brown crap in there, and especially on the glass of the tank its like built into the substrate near the glass. How can I clean that out? I try using a gravel vacuum but it just pulls all the substrate up and when I let go it makes a giant pile and ruins my layout. It also sucks up my plants sometimes.
 
I am very frusterated when changing my water because I know that when I go to clean my gravel I can only get like 3 inches of gravel because I have to re adjust everything. (I have a 20 gallon long btw). How can I really clean my gravel good and suck up all the crap in there? Or just to get cleaner gravel. I noticed when I take my finger and mix it up a bit the brown stuff gets in to the water and I can just suck it up but that only works for small parts. Please help me. Thanks

 

[fluttermoth]

There are few things you can do.
 
First of all, try mot to worry too much about the brown stuff ('mulm'). As long as it's just fish poo, not uneaten food, it won't cause any problems, apart from cosmetically.
 
Try doing more frequent, smaller water changes, just cleaning one small part of the tank at a a time, for a week or two to clear out the bulk of the mulm.
 
Using a gravel cleaner takes practise! Try ; moving it in small circles above the gravel, so the milm swirls up into the siphon; push the gravel cleaner down into the gravel, but only in one spot, so you only pick up a little bit;  keep a thumb or finger over the bucket end of the tube so you can block it and let the gravel fall back down before you suck up too much, or if you get a plant; use the edge of the gravel cleaner to smooth out the gravel as you go.

 

[Byron]

Fluttermoth has explained the technique very well.  As for the appearance, this is something I noticed with the black Flourite substrate I had for a time in one tank; I could never get it looking clean on the surface.
 
The ring of brown/black/dark green along the glass below the substrate surface is normal with any substrate.  You could get a scraper and dig through the substrate to scrape this off, but it is not doing any harm and I never bother.
 
Organics in the substrate is a prime source of nutrients for plants.  This is where the majority of natural CO2 (carbon dioxide) comes from, and in addition to plant nutrients the substrate is also the home of many types of bacteria (aside from just the nitrifiers) that are essential to a healthy aquarium.  I tend to stay out of the substrate in planted tanks, except perhaps at the front in the open areas, but even then I barely pass below the surface.
 
Byron.