The problem with JI 3 is that the nutrients are likely to leach out into the water before there are enough plants to use it, hence the cyanobacteria get to use it in stead. If you have a very heavily planted tank, such as aquascapers have, it would be more likely to be OK. JI composts also contain ground limestone, which may be an issue (good or bad) in some cases. In addition, it includes peat which will eventually break down which might be a problem in the long term, e.g. if you hope your tank will not need redoing for several years.I'd recommend floating plants to compete with the cyanobacteria at first, although they don't do well if you have a high flow rate across the surface. 2 cms is quite a small depth of compost so may not cause problems anyway, the total volume of compost will be quite small compared to the water, I have 5 cms of soil in mine.
The Walstad method comes from a book called "The ecology of the planted aquarium" which is a very detailed look at the relationship between plants and fish in an aquarium. Unlike so much personal opinion expressed on the internet everything is backed up by proper scientific research results, all referenced fully by Walstad. You need a decent understanding of chemistry and biology to follow her logic.
Here are a few of the more interesting quotes from the book :
"Hobbyists can protect fish from toxins by hard work, e.g., frequent water changes, gravel vacuuming, and enhanced filtration. However, given a chance, plants can purify the water naturally and effortlessly for the aquarium hobbyist. In my opinion, the ability of plants to purify aquarium water and protect fish has been woefully underestimated.
…..... there is little to be gained from restricting the nutrient levels in the aquarium by underfeeding fish, changing water frequently, and cleaning gravel, but then adding it all back as plant fertilizers.
(Sounds like a lot of work to me.)
Frequent water changes should be unnecessary in well-established tanks. I change about 25 to 50% of the water every 3-6 months.
Gravel cleaning is detrimental in planted aquariums, because it prevents nutrient replenishment of the substrate.
Tanks with a soil layer and healthy plants will remove ammonia naturally, so bio-filters are unnecessary and possibly counter-productive.
Artificial fertilization with CO2, trace elements, and macronutrients is unnecessary if the tank contains a fertile substrate, the fish are fed well, and nutrients are not removed by over-zealous tank cleaning................... Despite warnings in the hobbyist literature, I always feed my fish well plus a little extra for the plants.
Having a ‘dirty’ aquarium that will support good plant growth requires a leap of faith. The hobbyist must believe that plants can help purify the aquarium.
Using soil in aquariums is a strong ideological barrier for many aquarium hobbyists. Here, I mean soils that ordinary gardeners grow plants in— garden soil (i.e., topsoil) or potting soil.
Although snails are frequently disparaged by aquarium hobbyists, they do not eat plants and are actually quite useful. Snails clean plant leaves of debris, algae, and bacteria. They speed decomposition, so that nutrients recycle more quickly to plants. Malaysian Trumpet snails tunnel into the substrate, thereby aerating the substrate. …. I keep snails in all my aquariums."
I set all of my tanks up with this method and have had no problems (including no cyanobacteria). The only exception is that she says that filters aren't necessary, while I use them as normal, mainly because my tanks are quite heavily stocked. I rarely change water or vacuum the gravel, fish are all healthy.
If you enjoy fiddling with your tank, adding one drop of this and two of that, 25% water change every week, then this is not the method for you. There is no one correct way to manage an aquarium but many (although there are also many wrong ways!!).
Topic: My Aquariums (Read 7600 times) 27 replies
February 20, 2015, 09:28:54 PM
