I've decided that I want to try a Walstad soil-based tank but I'm getting confused about what substrate to choose.
I've read Troi's introduction to soil substrates and he recommends peat due to the release of carbon-reach humic substances, if I've understood it correctly. Peat also interests me because my water is hard and alkaline (pH 8.2, GH 15+) and it would be nice to lower that slightly. I don't want to use John Innes or anything similar with lime in it that would raise hardness further.
I've read Aaron Talbot's guide to mineralizing topsoil and he specifically recommends NOT using peat although I'm not clear why. The mineralized route sounds equally interesting due to the reduced ammonia/algae and more stable substrate it provides.
I understand that Diana Walstad has used peat in tanks herself but does not recommend it due to problems she experienced with iron toxicity.
So I'm getting confused about these conflicting avenues of advice.
Apart from the acidic interaction with iron, is there any good reason not to use peat?
What do peat-based tanks do for iron supplementation, if anything?
Can topsoil (mineralised or otherwise) provide comparable levels of carbon for plants? Ideally I'm trying to achieve a tank where no carbon supplementation is necessary.
I've read Troi's introduction to soil substrates and he recommends peat due to the release of carbon-reach humic substances, if I've understood it correctly. Peat also interests me because my water is hard and alkaline (pH 8.2, GH 15+) and it would be nice to lower that slightly. I don't want to use John Innes or anything similar with lime in it that would raise hardness further.
I've read Aaron Talbot's guide to mineralizing topsoil and he specifically recommends NOT using peat although I'm not clear why. The mineralized route sounds equally interesting due to the reduced ammonia/algae and more stable substrate it provides.
I understand that Diana Walstad has used peat in tanks herself but does not recommend it due to problems she experienced with iron toxicity.
So I'm getting confused about these conflicting avenues of advice.
Apart from the acidic interaction with iron, is there any good reason not to use peat?
What do peat-based tanks do for iron supplementation, if anything?
Can topsoil (mineralised or otherwise) provide comparable levels of carbon for plants? Ideally I'm trying to achieve a tank where no carbon supplementation is necessary.