Here's a quick tip that may help a lot of people that keep popping up with questions about how to help remedy the above mentioned problems. I saw a couple videos recently uploaded to YouTube in the past month that addressed all of these issues, but there is a much more simple and far less expensive remedy.
If you aren't already aware of the benefits of filtering your water through sphagnum peat, here's an eye opener for ya...It naturally softens your water by trapping calcium and magnesium, the same way a charcoal filter traps impurities that you don't want. Doing so, aids in the lowering of your pH. If your system's nitrification process can't produce enough nitric acid to keep up with the hard water that you keep topping off your system with, you're going to have a really hard (if not impossible) time keeping your pH down. Pre-Filter your water through sphagnum peat or buy/build a canister filter to constantly circulate your water through it.
Secondly, the issue of algae control...Believe it, or not...The sphagnum peat filtration also aids in the control of algae. How? Well, as in one of the videos I mentioned, it was suggested that you periodically add humic acid to your system to darken the water in order to inhibit light penetration. Sphagnum peat not only releases tannins into your water, but also releases humic acid. Both of which tint your water a tea color and therefore inhibit light penetration (primarily in the blue spectrum, just like those BlueBlocker sunglasses).
Although humic acid is cheap, an RO filter is not - and they are extremely wasteful to operate. Save yourself a bunch of money and the burden of yet another periodic dosing regimen, with a simple and unbelievably cheap sphagnum peat filter.
did they mention any thing about ratios.. ie. peat to water volume?
I could offer multiple options on a flow through filter contraptions... im wondering if we need five gallons or 55.
On my 30 gallon experimental basement system, I just use a Rapids brand 80 GPH canister filter with a softball size nylon bag full of sphagnum peat in it. My neighbor with a 300 gallon Koi pond uses a 5 gallon bucket with about 2" of lava rock on the bottom, 8" of sphagnum peat and another 2" of lava rock on top to stop the peat from floating. Water is pumped in the top and drips out the bottom. I change my bag of peat every 2 months, she changes out her peat once a year.
have you noticed a change in hardness? im sure it works for the pH, but would really be most interested in the effectiveness on hard water. ...the best remedy for algae is Barley straw, a 1 gallon bag will do 1000 gal for 4 mos. it has to be use before algae is present. ..it has a natural algaecide... I think that may be the case with the peat as well.
I think I will do a 50 gallon control test on 5 gallons of peat, to see how the hardness is effected.
The only difference in hardness that I can tell is visually, I don't have a meter or test kit for that. The visual proof that I'm going by is that I no longer get calcium deposits anywhere and even the deposits that were on my lava rock and expanded shale have gone away...Interesting gimmick with the barley straw, that's a new one on me. I honestly have no idea if the peat is working the same way.
so if you strip out your calcium and magnesium whats going to keep your ph stable? if you strip out your mag and calcium there is nothing to stabilize your alkalinity and your ph will move around. Also if you have a cycled system that is up and running why would your ph be high? If you don't have enough nitric acid to counter act evaporation you need to add more fish. Maybe I'm missing something but this seems like it would mess up your ph over time if used.
No, I posted this to share with people a solution that I used to solve a problem in the beginning. My pH doesn't move around anymore, hasn't for over a year now. The point I was making is that people with these problems don't need to invest in an RO filter and adopt a humid acid dosing regimen as suggested in two videos recently posted on YouTube, that's all.
Here's a good read (http://pets.thenest.com/filter-aquarium-water-sphagnum-moss-12679.html) if the concept of filtering/softening water with Sphagnum Peat is an unheard-of solution. This method is as old as mother nature herself and is very common in the world of professional aquarists. If you're thinking that this method will strip out all calcium and magnesium, leaving your pH wandering all over the place, think again...Think what an RO filter would do, then ask yourself why anybody would ever use such a drastic filter for aquaponics. Heck, even companies like Fluval make Sphagnum Peat pellets specifically for this purpose and professional aquarists buy this stuff in the same quantities that they buy activated charcoal in. The chances of professional aquarists tolerating their pH getting repeatedly all out of whack, are an absolute zero.
I have a question are you using live or dead sphagnum moss? If it is live I would think that you would not want to change if out of the system because as you stated that it traps the minerals and helps with the ph as the dead part of the sphagnum decays it will release those nutrients back into the system as needed by the system and that is determined by what the water can dissolve out.
Fluval only sells dead moss, which is the brand I use. And yes, you do have to change it out. My small amount gets changed out every 2 months because my well water is hard as a rock. My neighbor only changes hers once a year because she only uses her well water when she does water changes on her 300 gallon pond. She also uses a much larger filter.
ah I see I misunderstood cool deal :)
I see, I have access to live sphagnum where I live. So when I get my system back up and running I will most definitely be using it. I had to tare my first system down due to moving.
Just got a text message from another AP friend of mine and he suggested building wicking beds that actually do recycle the water back into the system. Wherein, the beds are the Sphagnum Peat filters. The thought never crossed my mind before, but with that, you would not only have the benefits that I mentioned in my original post, but also - a perfect solution for implementing root crops into an AP system.