Compost In Tank As Alternative Trace Mineral Supplement?

[jamesbarr]

Hey everyone.

Just curious about what peoples opinions are about this idea Ive been having for my tank.

I have been reading that some folks put compost in their tanks substrate mixture at set up to boost growth in their tanks. This made me curious about the idea of using compost tea instead. If you arent familiar with the idea of compost tea you can find details quite readily if you Google it, however the concept is pretty simple. Put compost in a muslin bag, tie it off and hang it in a bucket of water. This allows the nutrients from the compost along with its trace mineral content to be released into the water, later to be used by gardeners as an organic replacement to chemical fertilizers. I want to skip the bucket step and just hang the bag over the side of my tank.

I have a worm bin composter in my home that I have been using over the course of several months. The compost is made up only of vegetable waste from our home along with coffee and tea ground and egg shell for to neutralize pH. I suspect that my compost may have a low pH from the coffee grounds. However I think that this would be a non issue being that there would be only small amounts of compost in the bag.

While definitive parameters of the compost in terms of TM, NP K are unavailable due to the drastic quantity of variables (foods introduced, amount of off gassing for N, so on) Its been consistently shown that vermiculite has a lot of minerals in it that are freed by the decomposition of plant matter and the digestion process of the worms.

I like to ere on the side of natural as opposed to chemical treatment for my plants/fish. At the moment I rely on my fish to produce enough waste to feed my plants, however (as I'm sure that you all know) my growth is very slow. I have a 60 gallon tank but probably only enough stock for a 40 gal. I'm not interested in buying a bunch of fancy equipment or fancy ferts.

Stock list:

7 serpea tetras

10 (approx) white cloud minnows

3 Rainbows (not sure type)

10 burma/zebra danios

3-4 random orphan fish

3 albino corys

2 albino hifin pleco

Plants:

Anubius Nana

Anubius Barteri (I think Im right on those two)

Cryptocoryne

Pygmy chain swords

jungle vals (languishing)

moneywort

java fern

I think I have it all covered.

So what do you think? Would you try it?

[ckmullin]

i prefer natural methods than a huge fert schedule however ferts do serve a very basic purpose. If its not in the water...if its not in the substrate...dose it. I would say don't use compost as there is too much organic material which will decompose and just cause other issues. In multi-layer dyi substrates as I typically do, I use a part of peat moss as a part of a base/middle layer but that is about it for organic material (almost but not all). You want a good zing to your tank grab some earthworm castings, if your Christian then the castings are holy just as the 10 commandment tablets.

Items that i've used and more or less currently run a 75 gal on: a bit of peat, zeolite, pearlite, diatonomus earth (kitty litter), iron powder, vermiculite the screened black soil and the earthworm castings (not in that order for qty ratio). I have nice growth and quite happy. Glutaraldehyde also does wonders for a planted tank.

So again, i'd say no to compost.

Edited January 27, 2013 by ckmullin

[jvision]

I added a bit of compost tea to boost the nutrients in my aquaponics system and lost all of the cherry shrimp in it. I don't recommend it if you have any sensitive livestock.

[nanmer]

I use worm casting in my substrate, Vals love it! My tiger vals are actually flowering. My 50 gallon grows plants like crazy and all I have in the substrate is a layer of peat mixed with worm castings and topped with sand. I have the tank in a south facing window and use no supplemental light (not a hint of algae anywhere). I add fertilizer when I remember, which may be once a month or two lol. The tank has been running for a year and a half now and growth has declined a bit, time to replace the substrate and go for another year or so. My other planted tanks are higher tech and do grow plants faster. If I had another south facing window, I would do this with all my tanks ... low cost and no work.

[jamesbarr]

I added a bit of compost tea to boost the nutrients in my aquaponics system and lost all of the cherry shrimp in it. I don't recommend it if you have any sensitive livestock.

I gave my stock list above. Would you classify any of my stock as sensitive? Im not really sure but I think that most are hardy.

When you did this in your tank, did you use commercial compost or was it your own? Some compost in stores are also supplemented with ferts. Just curious. Did you continue dosing the tea after the shrimp cratered? Any notable gains or loses (aside from shrimp) in your tanks productivity?

I think that I will set up an experimental tank for this. I have a 5 gallon set up here just getting dusty, Ill try it in that first and see what the results are and possibly expand from there to a 20 gallon tank I have set aside for my son. I think he would love it if his tank had more plant growth in it than Dads Ive never played around with substrates too much. My best results have come from playsand so far.

[jamesbarr]

I use worm casting in my substrate, Vals love it! My tiger vals are actually flowering. My 50 gallon grows plants like crazy and all I have in the substrate is a layer of peat mixed with worm castings and topped with sand. I have the tank in a south facing window and use no supplemental light (not a hint of algae anywhere). I add fertilizer when I remember, which may be once a month or two lol. The tank has been running for a year and a half now and growth has declined a bit, time to replace the substrate and go for another year or so. My other planted tanks are higher tech and do grow plants faster. If I had another south facing window, I would do this with all my tanks ... low cost and no work.

Super cool. I love hearing about low tech tanks doing well, since Im an aqua hobbiest on a budget Where do you source your castings from? I have a couple of worm bins running in my house at the moment. I am told that if a person lets the bin sit for a while when its full that the worms will eliminate all the compost in the bin and leave behind only castings.

[flyfisher]

I would be hesitant to use this compost tea in a closed system like a aquarium.Not all compost is created equal (to many variables)I have composted everything for years for use in gardens & lawns and seen the results some good some bad.So caution would be required in this experiment but would be interesting.

[nanmer]

I use to have two big worm bins but an extended holiday saw to their demise . I buy bags of it now from garden stores, I should really start a new bin but worms have really increased in price and are hard to find. What I would do to harvest the castings was to move all the compost to one side when it looked rich. I would place new peat/garden soil/sand on the other side and add scraps on the new pile. The old pile was left for a few weeks so the eggs had time to hatch and the worms to move to the new pile. I found that the process was much faster than a compost bin which never seemed to compost!

I would post a pic of my 50 gallon but I have removed most of the plants to my 110 tank.

My fish also miss eating red worms :cry:

[jvision]

The compost I used was my own creation. My system had 0 nitrates and I was losing plants in the aquaponics side, so I thought I could get some life in them w the tea. It helped the plants some, but killed all shrimp. I stopped using the tea and decided just to feed the fish more.

[jamesbarr]

I should really start a new bin but worms have really increased in price and are hard to find. I found that the process was much faster than a compost bin which never seemed to compost!

I found my worms on kijiji. I paid 20 bucks for mine, was a combo finished compost and worms and eggs. I also find that they really get through the food fast. It took me awhile to get the culture going in my bin as I think that I didnt get a pile of worms when I bought but now that they have gotten going I used the top layer from my bin to seed a new one and they are just going at it. Found this on calgary kijiji. There was also some adds for fishing worms on there as well.

http://calgary.kijiji.ca/c-buy-and-sell-hobbies-crafts-vermiculture-Worms-W0QQAdIdZ431173768

I would be hesitant to use this compost tea in a closed system like a aquarium.Not all compost is created equal (to many variables)I have composted everything for years for use in gardens & lawns and seen the results some good some bad.So caution would be required in this experiment but would be interesting.

Im kind of hesitant as well, which is why I will be doing the experiment on a tank I havent spent a lot of money on. My compost is vegetable waste only, so Im a little more confident using it than I would be using traditional compost with yard waste in it as well. Another thing that brings up confidence for me is that my worms are really healthy.

If finished compost is used than I hypothesize that nitrate levels shouldnt spike as the decomposition is very nearly complete. Ill have to buy a test kit and monitor this thing pretty well.

[jamesbarr]

If you are interested in how my compost is doing in my tank, I went with a walstad style tank rather than using the tea. So far, things are looking good.

http://albertaaquatica.com/index.php?showtopic=39222&hl=

[ubr0ke]

imo...inorganic ferts are safer for fish. You know what your adding. There are way to many examples of tanks using inorganic ferts with positive results to merit any worry. Organic, however is a risky endeavour.

I used to use worm castings. make sure to rinse then dry in sun to avoid ammonia cycle.

Edited March 13, 2013 by ubr0ke