Natural Fertilization Of Regular Soil?

I'm planning my 40 gallon breeder and I'm kind of stumped on the substrate I want to use. I'd like to do a planted tank (nothing overly heavy), and I want to try soil. I'm also on a budget, so I plan on getting just some regular garden soil from a box store somewhere. I'd dig up my own soil but it's full of pesticides, and frankly my yard doesn't really have a lot of places to dig it up in.

So I've been trying to do my own research, and I would love to get a tank where the fish waste and water column could perhaps replenish some of the nutrients in the soil that the plants are going to consume. The problem is, I don't like the look of gravel or lava rocks as a cap. I love sand, but I'm concerned that no waste or water is going to really penetrate the sand to fertilize the soil. I'd put MTS in the tank, but it seems like no fish stores (not even the boxes) carry them.

I want to avoid dropping a lot of money on substrate, because I'm really on a tight budget with this. I guess if I have to go with sand over soil I will, but honestly it seems like it's a waste of soil if it cannot be fertilized by the natural elements in the tank. I'd use all sand, but I've personally had a lot of difficulty getting rooted plants to stay in place or survive in my 10g.

I guess this is why people just use the expensive substrates?

 

For mts just go to a fish/pet store at night/evening. Look around for mts and ask if you can have some. I got around 50 mts for free from pet smart by doing that.

 

Or once you have 50 posts, go to the “Buy, Sell, Trade, Free” section here. Lots of people have extra mts they’ll send to you.

 

For mts just go to a fish/pet store at night/evening. Look around for mts and ask if you can have some. I got around 50 mts for free from pet smart by doing that.

None of the pet shops in my area have MTS .... they have all kinds of other snails, but not them.

 

None of the pet shops in my area have MTS .... they have all kinds of other snails, but not them.

They are not selling them but just look around for them in the tanks they have plants if they don't have assassin snails. You can just do what Fishcat said

 

What you're thinking of is cation exchange capacity, or CEC. There are a few nutrients such as NO3- (nitrate) that will not be affected by CEC, because they are anions (negative charge) instead of cations (positive charge), which is why water column fertilization is still a good idea.

Luckily CEC comes from humus and organic material, which soil is high in. I too wonder how CEC would be affected by a sand cap. It would entirely depend on how effectively water is able to reach the soil through the sand.

For more substrate info, take a look here:
Complete guide to substrates for the planted aquarium

The entire website is a must read for any planted tank keeper. Really excellent info. The author is Dennis Wong, examples of his (gorgeous) tanks and lectures are on Youtube

 

I second the advice of getting up to 50 posts and then start to haunt the “Buy, Sell, Trade, Free” section. You can get a wider variety of plants at good prices this way, and most of them have been grown submerged. Submerged do better in my aquariums as they are already acclimatized to growing underwater.

 

Okay, so another question (or maybe I should make a new thread on this... don't want to breach etiquette). Is there a way to wash pesticides out of soil? The soil here is some of the best in the country and would love to use it, but we have to treat the soil for termites and other pests so it needs to be washed out somehow. Said wash would probably have to remove lead too. I wouldn't want to remove the beneficial minerals in the process though.

After reading the link Mak posted, I think I'll just put an inch or so of soil (again, preferably from here) above a few lava rocks, and cap it with maybe 3/4" of sand. Hopefully the small layer of sand will be large enough to keep the soil down, but small enough to allow for transfer of waste to the soil, especially if I find some gritty sand somewhere.