Hi all,
The gravel is finer than it looks and the Geos have no problem sifting through it. A closer pic so you can see the gravel size, this is the smallest size i could get away with while having a lot of water flow
I still think the substrate looks too coarse for
Geophagus or particularly Cories. I also wonder whether the
Panque would be happier with a lot more cover on the bottom, either a really large wooden snag (with natural hiding places), or drain pipe caves (2 or more). It doesn't have to be quite this big, but this sort of thing <
http://www.planetcatfish.com/forum/view ... 1&p=158791>
You can still have sand in tanks with high flow, if you have a "sand in the filter" problem this is easily rectified by having a coarse pre-filter sponge on the intake, and the flow problem by using a mix of sand and and fine gravel. As the flow distributes the sand around the tank the coarser grains will be left in areas of high flow, and the finer grains in areas of lower flow. Areas of very high flow will have a bare bottom, and you can put larger rounded pebbles or cobbles there. In fact in the same way that a river would sort sediments.
I got this idea from one of Haarvard Stoeres' great photo postings, where the current had sorted his substrate.
![Image](http://i200.photobucket.com/albums/aa237/HaavardStoere/usm1000_0042.jpg)
<
http://www.planetcatfish.com/forum/view ... rd#p177140>
Even in high flow tanks you should be able to move the decor around to give a flat spot where suspended fine sediment, faeces etc will accumulate. Put a piece of flat slate there, and then you can syphon out all the debris.
cheers Darrel