Q about Kuhlis with sand and NPTs

[ALX]

it was suggested on here that I put sand in my tank for my 4 kuhli loaches. Right now they have just a light layer of sand that ends up on only half the tank floor.

I want to make a good home for my loaches but I really don't want a whole lot of sand on the whole tank. So I was thinking of making a short retaining wall on the tank floor so they could have a nice beach in the front but I could still do something else with the other part.

I was considering making it a mostly natural planted tank (NPT) with some soil covered by small rocks for the non sand part. I never made it this way before because I did not want the loaches to tunnel in it and make a mud mess. BUT.. if they have their big sandy beach they might not be interested in the gravel and dirt... They have a sward plant in a glass bowl with dirt and gravel that they don't mess with right now but it may just be that they don't want to go in the bowl.

So.. do you think if a kuhli loach had the choice of either sand or gravel on dirt it would choose sand?

And also, could I plant stuff in sand and have it grow in a low maintenance planted tank?

[Diana]

I would make the divided substrate you are talking about. Use rocks and expanding foam to build the retaining wall for the best separation, though the foam will show through the front glass. I have tried it without the foam, and the sand sifts its way through the rocks and mixes with the planting media.

Sand does not hold the nutrients very well at all, especially compared to soil or specially designed planting media. Keep the sand free of plants for the Loaches, and plant the rest of the tank.

[zmo63]

I did this in my kuhli tank, just like Diana suggested. I used eco-complete on the back half of the retaining wall, and pool filter sand on the front half. The kuhlis are equally active on both sides of the wall, but they only burrow in the sand (I don't think they can in the eco-complete). They also sift the sand through their gills a lot, but just seem to nose around in the eco-complete. All in all, I've been very happy. Just a warning though - my retaining wall has a couple of low spots between some of the rocks, and the kuhlis like to go through those best - so the eco-complete has started invading the sand in some places. I just sift out the larger particles and put them back on the other side of the wall.