Since i have had the tank up i have black and white gravel. They are almost the size of a pea maybe. I cant stand the b and w look and would rather all black as i am going to plant some bulbs so i want to get this done soon. My main ? is since the aquarium is cycled and by removing the current gravel to put in black gravel, will there any danger to this. Is sit something i shouldnt even try? Also ive read plants like sand as it has nutrients in it, but ive read cleaning it and making it stay looking clean is a PITA. Is gravel ok for the plants and is there an in between. Something that isnt as big as gravel but bigger than sand?

You can switch out your gravel if the filter is cycled,just expect a mini cycle.As long as you dont add fish as soon as you switch itll be fine and you may not even notice.

I have used sand,its not that hard to clean.i think its easier as you just have to hover the vac over it a little to get the poo or whatever to come up.Also periodically poking it in places will keep it from forming anaerobic patches.

Certain plants will be happy with whatever,but a good alternative,is Eco complete.Its kinda a mix of gravel an sand,making it easy to plant into.Also its a nice dark color so it looks great.

Honestly I dont vacuum my tanks,except fry tanks and thats because they are bare bottomed.If you have a nicely planted tank,then the plants will get more benefit from the gravel being left alone as it will use the feces as fertilizer.

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"Come to the dark side....we have cookies...and filters/heaters/and water changes!"

i saw that eco complete it looked really nice. Ive read people will take the old gravel and put it in a pantyhose and hang it in the tank for a while. Is that nessecary and if so how long should it hang in the tank. Also, what is anaerobic patches?

Yes you can add some of the gravel in panty hoses.It helps seed the new.you wont need it in there for more than a few weeks tops.

Anerobic is where patched of air form under the sand and this causes the air to be toxic under there,because of lack of oxygen.Basically bacteria gets trapped there and cant breathe so they die,or thats what I was told.I am sure someone else can tell more on it than me.

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"Come to the dark side....we have cookies...and filters/heaters/and water changes!"

Maj nailed it... Your substrate is the predominate bacteria host.. your filter media comes in 2nd place IMHO... Doing the pantyhose thing works well...
Substrate.. I swear by Pool Filter Sand. It's graded to a consistent size of .45-.55 mm. This allows water to flow thru it unlike the common playground sand which will compact. PFS is graded to ALLOW water to flow thru it. Plus your plant roots will find it easier to spread out.
Cleaning?.. I use a python which I'm guessing most do and I find the sand will get about 1/2 way up the chamber before falling back to the bottom... I've a 125, 75, 55, 3 29's and a 30 set up in this manner..
Bill in Va.

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12 Tanks, 900 gallons. Discus/Angels/Malawi/Lake Victorias. Just added a 135 & 2 - 29's..