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Worm castings in an aquarium


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So, i've been playing with dirted tanks recently. My first dirted tank was a little dissapointing with plant growth and produced a lot of tannins as i did not sift the organic miracle gro. A was asking around about dirted aquariums and someone on reddit recommended worm castings. This is the second time i saw worm castings thrown in to this discussion, as a comment on an md fish tank video recommended this as well. That said, there isn't that much out on this stuff being used in aquarium and it has never been mentioned on this forum. Has anyone used it? If not, i just did.

Well it was actually about a week or two ago so i can confirm it isnt gonna just kill everything. What drove me to try it, besides simply wanted to try something new, was a few things. First, it contains no wood chips and no need to sift. Second, it is almost entirely water insoluble nitrogen, which (i think) is what you want. However, the biggest reason, is this line of thinking. Composts and soils contain things like woodchips and eggshells to be broken down by beetles and worms and such, things not necessarily present in a fish tank, So, why not just skip to the good stuff, the worm castings?

For those unaware, castings is just a nice way of saying poop. Thankfully, worm poop looks, smells, and feels just like dirt, since thats basically what it is.

This is my setup. A 20 gallon with 4 lbs of worm poop. Im pretty happy with the scape. My brother helped me with the rock formation. To be clear, he told me where to put the rocks, he didnt help move them. My brother is the strongest person i know and he makes me do the heavy lifting. 

The stocking is all fish i already had in this tank. Some mollies, a couple tetras, a swordtail thats growing out until i trust in can handle its older siblings, a red tail shark i was planning on moving to a larger tank once it got to big, but its been like a year and hes still small. And a bn pleco.So, not a stocking i would necessarily recommend, but it works.

The plants are dwarf sag, melon sword, pearl weed, anacharis, some type of ludwigia i think, tiger lotus, giant hair grass, the onion plant thing, and water lettuce. Some plants from other tanks, some plants from the previous scape, some new plants. I wanted a wide variety to test out the worm castings. 

The like is the nicrew classicled


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I have used worm casting in two aquariums.  The first seemed to work very well. It was my first planted tank so not much to compare to.   My crypts were growing like mad, they were consuming the aquarium.  I ended up pulling them out because they were so out of control and spreading fast.  That caused a huge mess in the tank from uprooting plants.  You better like where you plant with dirt/ worm castings bucase you dont want to move anying.The second is a 5 gallon the I just set up yesterday. Giving dry start a try, so time will tell on that one.  

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I've not tested these as fertilizer, but I do have some experience with it as a food supplement. You may want to observe how any of your shrimp, snails, or crayfish deal with the worm castings. Many years ago I kept land hermit crabs. What was their favorite treat? Worm poop. Didn't matter what else I had on offer. Fresh fruit, bit of chicken, meal worms... nothing got their attention faster than worm poop. Something about worm poop makes detrivores ravenous.

Which I guess just goes to show: Even in the aquarium, "the spice must flow".

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