Planted Aquarium Substrate- How I do it and why…

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The importance of your substrate in the planted aquarium can not but under estimated. I heard Greg Moran of Seachem say that, “Plants absorb 40 to 400 times more nutrients though their roots than through the water.”

I haven’t done nearly the research that the folk at SeaChem have. But I have kept enough planted tanks to know that you substrate matters. SUBSTRATE IS THE MOST IMPORTANT PART OF YOUR PLANTED AQUARIUM.
Yes- More than lighting and more than CO2.

When I first set up a tank with dirt I was shocked at how well the plants grew in it. That tank was my 125 gallon tank which I ran “high-tech.” I had over 250 watts on it and was running CO2. So there were other variables that were contributing to my great plant growth in this tank.

For step by step instructions – check out my Dirted Tank Guide!

It wasn’t until I started running tanks with dirt in “low-tech” fashion that I began to realize just how important dirt in the substrate of the planted aquarium is. These tanks were ran without a large amount of lighting- two bulbs max. None of them had any CO2 for the most part.

With these variables aside I was able to determine that the nutrient rich substrate was infact the cause for my great plant growth.

So then the question become, “Dustin-How do you do it?”

I have made several videos about this and will attempt to describe how it has been done in my tanks.

The first step is to use dirt as your bottom layer of the tank. Yes- It goes glass, then dirt. I recommend using organic dirt from your local Home Depot or Lowes. You can see in the video above what brand I use, though I am not partial to any brand. But you want to make sure it has NO FERTILIZERS in it.

This is key. But you can’t just put the dirt right in the tank without an preparation. Well..You can, but you will have a mess on your hands no too long afterwards.

I recommend taking the dirt and soaking it in buckets to get all of the air out of it. If you have air in your bottom layer you will have bubbles coming up though your tank which will bring unsightly clumps of dirt up with it. SAVE YOURSELF THE TROUBLE. Take the time to rinse and remove any wood chips from your dirt. My buddy Kirt pushes his wet dirt through a screen to make sure that it is a super fine grade. I personally don’t do this, but I do see the value in it.

What you are trying to do is get it to a muddy state, not too watery, but the consistency of pudding let’s say. While watery would be trouble at this point, you can always let it dry out a little, or add more dirt. Either way is better than having it be dry. Dry means trouble when you add the regular gravel down the road.

Try to cover the bottom of a tank with about 1.5 to 2 inches. This is more than some recommend, but my experience has shown that if you don’t put this much in, the plants will “eat” the 1 inch layer too quickly. I will say that this is what happened to me on the 125 Gallon planted tank, which was running “high tech” The soil under the substrate might have lasted longer if I wasn’t running the tank a full throttle with CO2 and heavy lighting.

They are other ingredient that are worth adding to the bottom layer of soil at this point worth mentioning.

Clay is my favorite add on. I use potters clay from the local craft store. I have show it on a video here. I won’t go into the chemical properties of clay in this article, though I will at some point on this blog. Basically clay helps maintain the iron levels in the substrate. IRON is the KEY. There is Zero point in spending high dollar on liquid fertilizers that go in the water, when you can take some time up front, and get the iron in the substrate where the roots were meant to take it from.

Again — “Plants absorb 40-400 times more iron from their roots than the water”

So after we have added our iron, I like to also add something that is going to bring my KH up. That is Carbonated Hardness. Simply put the plants will eat all of the salts and minerals our of the water which will hurt your fish. Another reason not to use CO2. It will lower your KH and shock the fish. NOTE: Obviously the plants love the CO2, but we are looking at the whole tank here.

To keep the KH up in a tank you can buy expensive KHup from a petstore, or you can get creative. I have used old crushed coral from my reef tank, I’ve also smashed up oystershells and used them. Calcium helps keep KH up. Both of which are found in crushed coral and in oyster shells. I will have to work on the ratios, so if you are reading this and want to know how much to use just post a comment and I’ll tell you what I’d use based on the tank size. A handful of crushed coral in the dirt of a 55 would work…(rough guide line)

So this is what I recomend for the bottom and most important layer of your planted tank substrate. Part two is adding the gravel over it, and the routine involved…

Yes there is more work after we add water…but its worth it…

Baby is up and crying… more coming..

Ok. So now that we have added the soil to the bottom of the tank we are going to need to cover it up with some gravel. I recommend using some very fine grade, (but not sand) gravel. Pool filter sand works pretty good. We are looking for only a few millimeters here, nothing much bigger. You can go with “normal” gravel from your local fish store. It comes a little bigger then I would like, but works and gives you options.

If you are setting up a 55 you will probably need around 40 lbs of gravel or so. I like to buy the 25lb bags because its slightly cheaper that way.

You are going to want to place about 30 of the 40 pounds in first. I like to save 10 pounds to “touch up” the tank after I add water. Otherwise you might have some dirt that comes up and nothing to cover it with…

The best method for adding water at this point is the SLOWEST METHOD POSSIBLE. You DON’T want to mess up the dirt under your gravel. A dinner plate laid over the gravels works good. I have also laid a plastic bag over the gravel as well. The point is to not mess up the dirt under.

Fill that sucker up SUPER slowly at first. There are going to be bubbles at first, thats fine. Add water and push down on the gravel to help them come up. The more you get air out here, the better you will be down the line….

Fill it up 50% and push on the substrate, getting more bubbles out…

Add as many plants as you can at this point. Plant the hell out of it…..

The more plants you add, the more nutrients will be taken out of the water column. Don’t worry if some of the plants get shocked and loose some leaves, this is normal…

Drain it, and fill it up again.

You are going to want to let it sit with the lights off but filters on for a few days. Drain it, and fill it again. To be safe drain and fill atleast 3 times. I’ll say it again, Drain and fill it 3 time before you think about adding any fish.

Personally, I let my tanks sit for about a week or more with just filters on and plants with an air stone before I add any fish. I have added fish as quickly as the next day, but I don’t chance it if I have the time.

ASK ME QUESTIONS, What i miss?

For step by step instructions – check out my Dirted Tank Guide!