I plan to set up a new planted tank but am not sure how to go about making the substrate.

I was planning to use peat, clay, vermiculite and potting soil. Is that a good combination for a planted tank with tetras (neons mostly) ? Should I layer or mix them together ? If I layer, what order would be best ? Should I add sand ? I know this will be an organic mix so I will have to change it out about once a year. Also, should I top it with fine gravel or is that not important ? Sorry for all the questions but I've never really done planted tanks (atleast not with any success) and since I'm likely to do a larger tank (75 gallon +) I'm trying to keep the cost practical.

Thanks in advance for any input

Well I put in my potting soil first (make sure it's organic), then I'd put the peat, then the clay and probably the vermiculite (it's gravel-like right?). But honestly I'm not of much use to this. I just use potting soil and paver's sand.

You'll want to look up the "Walstad method" for using organic potting soil. It's dangerous, because without proper layering the soil can leech excessive amounts of nitrates and phosphates into the water and wipe out your fish. That being said, most hard-core planted tank people go with the Walstad method because the massive amounts of fertilizers in untreated potting soil makes their plants go bonkers.

I wouldn't use peat - it doesn't do very much at all. I would use potting soil as a bottom layer, and a clay compound like Safe-T-Zorb, Fluorite, Eco Complete, PC Select, etc. as the top layer. You could do a middle layer of sand, but there's really no need.

That's just my thoughts and speculations. I thoroughly encourage you to research a LOT more. There's options like mineralized topsoil (I'm currently using it), kitty litter, etc.

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Officially fishless until after the move....tune in later for details!

The main reason I wanted to add peat was for the fish, not the plants. My water tests hard-very hard and from what I've read it seems that peat is a good way to naturally lower hardness and tends to mimic natural conditions for tetras.

I will definitely be doing more research and reading more into the Walstad method. My main concern was actually leeching. The article I found rather helpful was Substrate materials for the planted aquarium | Aquariums Life

But it doesn't really give much info in the way of layering or mixing. Worst case, I may just play around with different ideas in a smaller tank until I figure out what seems to work best. My goal is a tank that makes my tetras happy (they're the only fish I keep other than a few clean up crew) but also works well for plants.

Thanks much for the advice.

Peat is a good way to soften the water, but just like driftwood leaching tannins it's effects do go down over time. I don't see where natural soil is dangerous. Whether it is layered or not the nutrients will be on the water. A layering does not do anything other than keep the loose stuff from flying about or clouding up the tank. If you do use peat, I would just use enough to barely cover the bottom, or mix it with the soil. FWIW, I had no trouble keeping my Cardinal Tetras in 8.2ph, 10dkh, 10dgh for 3-4 months before I moved them to a different tank.

I'm speaking from a situation that one of my local hobbyist friends got himself into, but he might not have been using organic potting soil. I seem to recall he tried with Miracle Gro or some sort of fertilizer, and had fertz overwhelm the tank and wipe out his fish.

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Officially fishless until after the move....tune in later for details!

I just use sphagnum peat moss, sand, pc select in 1" layers from bottom to top.

Not sure and no good feelings for vermiculite.

I have found the peat does keep kh at around 4 degrees and gh at around 9 degrees. With just sand both rose to high levels.

My pH is 8.4-8.8 but then I do no water changes and use not mechanical filters or circulation.

just some thoughts.

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fw leiden since 1979, fo salt since 1979, mixed reef 55g 2002-2009. Strong emphasis on the tank taking care of itself. Balanced with plant life, no water changes, tap water, no filters in FW. Only dosing calcium, alk, mag in marine reef tanks. http://www.aquariumforum.com/f15/my-...ods-26410.html
recent tanks (till 2009) 7 years- 10g FW leiden 7 yrs, 55g mixed reef 7, 2 yrs, 20g FW leiden, 10 g fw leiden , 29g mixed reef, current tank 55g leiden

Natural soil would be much better though.