What type of substrate should I use in my 55g Oscar tank?

ive got 7 tanks with all 7 of them got diffrent substarte in them.

my 100g tank has black finely crushed slate in the bottom and it is the easiest to maintain as the crap lies ontop of it and doesnt seep into the substarte so bassically u just vacuum ontop of the sand and its all clean again.

ill go with n fine sand or stone.

Out of all substrates I have used including sand. Have found really fine river gravel is best, about 3mm size.

I use river gravel in all my tanks i just find it more appealing to me sand seems to go everywhere when i use it so i stick to gravel.But like vbaby said sand is just as good.They both have good and bad points it comes down to personal preference i think.!

My oscar likes to dig in the corners of the tank. When I had sand and cleaned out filters they were full of the stuff. Fine river gravel is still fine enough for my 'O' to digg / root about in.

It is still heavy enough to avoid being dragged up into filters. Is also very easy to keep clean with syphon cleaner.

I say gravel is the best. I have just set up a reverse undergravel filter (take the outlet from an external filter and connect it to the upright tube of an UGF) about 4 weeks ago and so far the gravel is very very clean with no need to gravel clean. You will need a gravel tidy as the oscars will dig

I still have not gotten my 150 because we are awaiting the carpet. But meanwhile I have been trying to do some planning.

Regarding the gravels ~ I had seen in my aquarium store
a very nice larger size gravel (pebble) the size of a
dime to a nickel. Its very nice. But I was wondering
how would that be in a tank since it really does not sit close, compact close like sand or smaller gravel. Will it be able to be siphoned clean with the python vac since the stone is heavier ~ will it be able to lift it. What about the fish who like to dig? Will this be a problem? This gravel is really nice and natural looking.

Or, if its not a good idea, what do you think about mixing this with a smaller/regular size to fill in the gaps?

Thanks for your help.

If the shop has some of the gravel you are looking at in a tank ask them to show you them cleaning it with your gravel cleaner. If it works then you will know you will be able to keep it clean

Personally i wouldnt go with anything bigger than pea sized as oscar do like to dig and rearrange the gravel and they might not be able to with larger gravel