mixing substrate for kuhlis and plants

[zmo63]

So I bought a 40 gallon breeder, and the plan is to upgrade the kuhlis that are currently in a 20 gallon high. It was a craigslist purchase, so it came with lots of used extras, and one of the extras was a large bucket of black sand. I asked the lady if she knew what kind of sand it was, but all she knew was that she got it at the petshop.

It appears to be really good sand. Very fine, but heavy, perfectly round and soft, and all the particles are the same size. From reading many past posts, it sounds ideal. I put some in a cup of water, and it all sank immediately. I'll check the pH on the water when I get home from work, just to make sure it's inert (that's how you tell, right?)

So I have a couple of questions. First, I don't think there's enough sand to do a bed deep enough for plants. I've looked in pet stores and I don't see anything similar. I was wondering if I could mix it with the eco-complete I'm using now. I LOVE the eco-complete, but I don't think the kuhlis do. What would happen if I did a mixture of the two? would the sand all go to the bottom? Would it compact too tightly for the kuhlis to burrow? What if it were 60% sand, 40% eco-complete? or 70% / 30%?

Another option would be to find a natural colored pool filter sand, and mix those too. Or just scrap the black sand altogether and do straight pool filter (this will make me sad, because I'd like a darker substrate).

My second question is about plants and sand. I've never used anything other than eco-complete, and I worry about how to keep the plants healthy if the sand doesn't hold nutrients. That's part of the reason I was wondering if a mix of the two might work.

I know many of you out there are keeping beautiful planted tanks on sand, so tell me what I need to know! Root tabs? Extra ferts? Layered substrate (does that work with sand)? Easier plants? I'm new at this

Thank you!

[NancyD]

Sounds like Estes brand, not one I've tried. I have very shallow pool filter sand in my kuhli tank between 1/2 & 1 inch but they don't dig, more like "tummy tracks" on the surface. It was my first sand tank & I was worried about anaerobic bacteria pockets.
I have crypts & small sword plants I feed occasionally with root tabs (both macro & micros). I had to mound up the sand a bit around them & weight with small rocks at first. I can't grow stem plants in it, well, rotala stayed down eventually but was stunted (low light too). I have java windelov & anubias on wood & rocks the kuhlis poke around.

[lf11casey]

You could always make little tubs with milk jugs. Just wash them out really well and cut them up, just use the bottoms filled with Eco-Complete and put your plants in those. Then use sand in the rest of the tank.
Or cut the jugs into strips and use those to seperate the Eco-Complete and sand.
The good thing about the jugs is they're easy to get and you can cut them to the height you want.


Casey

[Diana]

You could make a small retaining wall out of rocks. Put the EC in the back of the tank, and bring some forward on both sides. Perhaps 3/4 of the tank would be EC. Leave the front open, and fill that area with sand. You could go 2" or more of EC for the plants, and leave the black sand lower.
Use expanding foam to hold the rocks in place, and fill between them. It is easy to cut when it is dried, and is fish safe. It is available in black, too, from pond supply places. (Brick and board stores or on line)
If you just had the rocks, nothing to hold them stable the higher EC would slowly push the rocks closer to the front of the tank.

[zmo63]

Thanks for the replies, everyone. I think it is estes sand.

I think the idea of a retaining wall to have eco-complete in the back for stem plants might be a good compromise, but first I've got to figure out what this tank is going to look like and where all the plants will go (everywhere, I expect. milk jugs + retaining wall might be the ticket). The 20 gallon that this tank is replacing has a lovely carpet of dwarf hair grass in front; I doubt it will be transferable to a sandy tank

While I was googling estes sand, I found mention of mixing sand with sphagnum peat. I'm very intrigued - anyone have thoughts on this?

I might get a few bowls out and experiment with small samples of different eco-complete / sand mixes. I'm expecting that since no one seems to have done it, it's not a good idea, but sometimes I need to learn for myself.

I'd also wondered if maybe eco-complete with a generous layer of leaf litter would satisfy both the plants and the kuhlis.