Spring Planning and Aquaponics Phase 1

It’s still snowing and below freezing here in zone 4b, south central Minnesota, but it’s definitely time to get on the ball planning for the full exposure growing season!  We’ll be doing two main gardens, one at a relative’s house in Hastings (800+ sq ft) and another at our community garden plot in Saint Paul (300 sq ft – just got our confirmation Wednesday!)  I may also try a few things on our balcony, which is mostly shaded except for one corner which sees full sun – I’m thinking mostly greens/herbs and maybe a cucumber in a wine barrel or grow bag.


We’ve got seeds!  I went into the season with a ton of saved tomato and herb seeds, and not much else, so I spent some time and hard earned cash over at the Seed Savers Exchange website getting some serious edibles and companion plants.  We’ll be doing a couple of “three sisters” style plots this year, as well as a ton of brassicas, tomatoes, cucumbers, herbs, and other greens.


I decided to play around with some different seed starting media, rather than buying a mix. I started out with way too much moisture in all the mixes, so I had some mold early on (these seedlings were started just under 3 days ago), but they seem to be doing better now.  I decided to start in a mix of 100% vermiculite and then up pot to an organic potting soil mixed with vermiculite and coconut coir once the true leaves start to come in.


I set up a starting station with a Super Sprouter 2 Tray seedling heat mat, a Hydrofarm Jump Start 64W T5HO single bulb fixture, and a Hydrofarm Digital Thermostat to keep the temperature under control and consistent.  With just over $100 invested and the capacity to start 140 seeds at a time, I feel like I will be saving about that much by not buying starts this year alone, as well as the added benefit of having starts to give away to friends!  This also lets me grow what I want to, not just what is available at the local nurseries.


In the meantime I got our living space rearranged a bit with the goal in mind of setting up my initial aquaponics “tester”.  I will be using a 30 gallon all glass aquarium on the bottom shelf of its stand with a 50 gallon rubbermaid HDPE tote from a local home improvement store (under $20.)  On order is a 300 gph (gallon per hour) water pump, necessary to lift the water nearly 4 feet up into the grow bed.


I’ll be growing in expanded clay pellets purchased from my local hydroponics store – this was the pricy bit at just over $30 per 50lb bag, but it is inert and reusable for future projects.  The advantage of this is that it will be very easy to move plants around without damaging them, and it is much lighter weight than the equivalent of gravel/pebbles.  It should also be significantly cleaner than any of the cheaper options, saving me some work up front.

After the pump arrives I will start assembling plumbing hardware, including a ball valve to limit the flow of water.  I will also start building my bell siphon, which will eliminate the need for a pump timer in my flood and drain system.  I will also be purchasing a 4-bulb shop light fitted with full spectrum fluorescent tubes (4′ length) and hooking up some sort of pulley system above the grow bed – possibly ceiling mounted.

If you’re interested in seeing what some other folks are doing on a similar scale, both PhillyAquaponics and ImpossibleFrontflip over on YouTube have a great series of videos on the subject – it is really incredible how many people out there are playing around with this idea, on a wide range of scales.  There are also some great discussions to read over at Backyard Aquaponics, and the crazy awesome folks over at Permies even have an aquaponic forum.

Also on my mind have been wicking beds – a pretty ingenious way to have a low maintenance garden and even use your aquaponics/aquarium water to feed more plants.

And finally, I had a good time playing around with Garden Planner Online, a really easy (and free to try) piece of software to design your garden by the square foot or square inch (or square meter, etc) – it even lets you print your garden plans to pdf so you can save and look them over later.

Good luck with your spring planning!

What’s in your water? (part three)

In this installment on water, I’m going to report on my findings from my water treatment experiments so far.


As a disclaimer I am not a scientist, nor should my methodology be viewed from that perspective.  I am a home hobbyist, using the somewhat unsophisticated and mostly uncalibrated testing material available to the aquarium hobby.  At best my results should be viewed with skepticism and are only presented here to give you an idea of what is working for me.  Time will be the ultimate test, as I start to put this “vitamin C water” into use I will no doubt have issues that arise, and I will do my best to update as I continue to learn.  You will notice I have primarily focused on chloramine and ammonia in these tests, as they are the two most concerning things in my water as far as fishkeeping goes.  Another area of some concern and controversy is fluoride, but I’ve chosen not to focus on that because the levels in my area are very low – around 1ppm.  At these levels the effect on plants and livestock should be fairly minimal.

Before I get on with the results, I want to do a quick review of the nitrogen cycle as it applies to fish tanks, so that the test results will mean more to you as you look them over.  A fish in an aquarium lives in a closed system, meaning everything that is added to a tank stays in the tank until removed by the fishkeeper.  This means that the smaller the tank, the smaller the change required to throw the system’s balance out of whack.  This is why the “betta fish bowls” that are still being sold at pet stores everywhere are such a horrible idea.  They are so small that the slightest bit of contaminant that is introduced will probably kill the fish.  For this reason, I try to keep fish in tanks no smaller than 10 gallons.

As you feed your fish, you are adding material to the closed system, meaning it’s not truly “closed” after all – there’s now an “input”.  The fish then eat the food they need, and any extra sinks to the bottom and begins to decompose.  After the fish digests the food, they must excrete their waste product just like every other organism, so this also sinks to the bottom of the tank and begins to decompose.  The primary chemical result of these things breaking down is that ammonia is released into the tank water and substrate (e.g. gravel). Ammonia, it turns out, is toxic to life in amounts as small as 0.5ppm (parts per million) and at that level will kill fish within a day.  So how are those fish in the tanks at the zoo alive?  That’s where the nitrogen cycle, or biological filtration, comes in.  In a natural setting, like a lake or pond, the dilution effect is huge, but the water is also teeming with bacterial life that live and thrive by eating ammonia.  These are called nitrifying bacteria, and they are the next step in the nitrogen cycle.  When established in sufficient numbers they consume some oxygen and a huge amount of ammonia – easily up to 5ppm in a short period of time in an established tank, which is more than a safe load of fish in an aquarium will produce.  But we’re not done yet, these organisms which eat the ammonia then excrete a waste product called nitrite.  This by-product is also toxic and dangerous for fish at any level, as even small amounts under 0.5ppm can damage their internal organs.  Levels over 10ppm are considered instantly fatal.  So once again we need another form of nitrifying bacteria to come along and eat the nitrite – and that’s exactly what happens.  Once the second round of good bacteria are established, the nitrites are consumed as quickly as they are produced, and thus we get their waste product – nitrate.

Aha!  Something any gardener will recognize as an absolutely essential macronutrient (aka fertilizer) for growing healthy plants!  And also the primary reason aquaponics is so interesting – because with an established system you are working with something almost completely self contained.  The only input is fish food and top-off water, and the outputs are all edible or compostable!  Nitrate, it turns out, is not only essential for the growth of plants, but is also only toxic to fish at levels over 50ppm.  This gives us a much greater margin to work with, and a great deal of nutrition to feed our plants!

In a typical aquarium without a huge mass of green plants to soak up the nitrates over time, the fishkeeper is required to do a water change – remove a portion (10%-50%) of the nitrate-rich water from the system and replace it with freshly treated water from their water source.  For lightly planted or unplanted tanks over 10 gallons, this needs to be done as frequently as once per week.  That’s a lot of water (and fertilizer) down the drain!  But once you start working with a tank stocked full of green plants to soak up the nutrients, all of a sudden there are fewer water changes to do, and more time to work on more interesting projects – like growing food!

So… let’s get to the results.

First, I am happy to report that, at least for my area, my tap water test results did not stray far from what the city I live in claims on their annual report.  The water coming out of my tap is safe to drink as it is, at least by their guidelines, and any additional filtering and treatment I do will only make it safer for my family, my plants, and my fish.  Let’s remember that the levels of contamination we’re talking about are incredibly small… we’re talking in parts per million, not in percentages.  Also for us humans, our digestive systems are fully capable of processing such a small amount of chloramine so that by the time the water is in our soft tissues no detectable levels are present.  For fish, however, who live in water 100% of the time, the chloramine is incredibly toxic – it passes right through their gills with every gasp for breath, coming into direct contact with their soft tissues.

For my tests, I started with two 5 gallon buckets of water straight out of the tap at approximately room temperature.  Into bucket #1 I mixed the standard amount of commercial water conditioner I always use when filling my fish tanks.  Bucket #2 was left alone for the time being, so that I could test the tap water.  I then took samples from each bucket for chlorine.


On the left is bucket #1 (treated) and on the right is bucket #2 (untreated tap water).  This confirmed that the water conditioner was doing its job and removing all traces of chlorine and chloramine from the water.  It also confirmed that I had about 4ppm of total chlorine with maybe 0.5ppm of free chlorine present at the tap.  To determine how much chloramine is present we simply subtract the free chlorine value from the total chlorine value for roughly 3.5ppm of chloramines in my tap water.  So, the water conditioner is great!  But…


I’ll keep using this stuff on my fish tanks for now for two reasons.  First, it not only deals with the chlorine, but also the residual ammonia from the chloramines.  Second, I don’t yet know what the long-term effect of my alternative solution, ascorbic acid, will be on the aquarium ecosystem and its inhabitants.  I am eager to get an alternative figured out soon, so that I can start feeding my plants the wastewater from my fish tanks.

Next, I thought I’d check out what my standard pitcher-type charcoal filter was doing about the chlorine in my water.  I took about 1.5 quarts of water from the untreated tap water sample (bucket #2), and let it run through the drinking water filter.  It took about 7 minutes to filter this small quantity in a fairly new filter (changed maybe 2 weeks ago.)


From left to right we have treated water (bucket #1), filtered water (bucket #2 post-filter), and unfiltered water (bucket #2).  It’s clear from this that even a modest pitcher filter is doing something, as I see only about 1 or at most 2ppm in total chlorine present after the tap water has gone through the filter – that’s up to 75% of total chlorine filtered out of the tap, not bad!  Given the rate of filtration and the fact that there is still chlorine in the water, however, means this is not a viable option for treating tap water for aquarium use.

So here goes the Vitamin C!


To deal with the small levels of chloramines coming out of my tap, I need to add just under 400mg of ascorbic acid to each 5 gallon bucket I will be treating.  You can find ascorbic acid in 500mg capsules that would make dosing a 5 gallon bucket a no-brainer, keeping in mind that every little bit of acid you add will shift your pH down proportionately.  My local co-op had an 8oz. container of ascorbic acid powder rather than the capsules, so I opted for that.  It was about $15, but at the correct dosing amount, I’m able to treat over 550 5gal buckets with one container.  I’m using a small fish food scoop and adding 3 of those, which should give me 350-400mg total dosing per bucket.  For reference, 1/8 teaspoon is approximately 500mg of ascorbic acid powder, depending on the grain size.

The ascorbic acid reacts with the chloramines in water, releasing three by-products:  free chlorine, dehydroascorbic acid (a form of vitamin C beneficial to living organisms), and ammonia.  So we’re not there yet!  The good thing about the conversion to free chlorine is that this compound is now able to evaporate, or out-gas, from the water.  This happens fairly quickly, and is why we used to leave our buckets of water out overnight to age before adding them to our fish tanks.  So we’ve replaced the stable chloramine with an unstable chlorine, which will evaporate out of the water… we’re getting closer – assuming this works!

To speed things up, after adding the ascorbic acid (roughly 375mg) to a nearly full 5 gallon bucket, I drop an airstone attached to an air pump into the bucket.  This aerates the water and keeps it moving so that all the chlorine will out-gas – it’s not necessary but ensures more reliable results.


I head off to work, and 9 hours later am excited to see the results!


Great success!  The test strip on the bottom is from the Vitamin C treated water, and shows no residual chlorine after 9 hours of bubbling away!  You can see the other test strips from earlier above, now dried out and less colorful.  I will be testing this further to see exactly how long I have to leave the water to out-gas before using it.

What about pH?  Did the acid I added to the bucket bring down the pH a dangerous amount?  Well, here’s the pH level before ascorbic acid was added…


Hard to say for sure, but I’d guess that’s a reading around 8.4 – which is fairly alkaline.  Next is after the test cycle was run…


That looks like about an 8.0 – so we’ve definitely dropped some pH, but as you can see from the “low range” test it has certainly stayed above 7.6 regardless.  As I mentioned earlier, it’s a benefit that my water started out fairly high in pH, so this small swing should not adversely effect the viability of the water for aquarium use.


I also tested for Phosphates, Ammonia, Nitrites, and Nitrates, just to be thorough.  Phosphates and Nitrites were, as expected, at zero.  Nitrates actually surprised me by coming in at just over 10ppm – I will have to monitor my tap water for a little while just to see if this drops back down to expected levels.  At any rate it is not enough to pose a problem even for fish, and should be a benefit for plants.  Ammonia is the only real area of concern, as there are detectable levels in the water now up to 2ppm.  This means that I would not want to take a fish out of its tank and drop it in a bucket of water treated with ascorbic acid, but the biological filter (or nitrogen cycle) in an established tank should be able to deal with this level pretty quickly.  Where did this ammonia come from?  Remember I mentioned that chloramines are chlorine bound with ammonia?  Well, we released the chlorine, and that left residual ammonia behind.

In conclusion, it looks as though Vitamin C might actually be a viable option for treating water in absence of aggressive whole-house filters, in order to remove chloramines which are otherwise difficult to get rid of.  The quantity needed is very small and inexpensive on a per-use basis, and this will allow us to raise fish and water our plants without destroying the necessary nitrifying bacteria which live in our soil and our fish tanks.

If you are interested in learning more about what is in your water, I encourage you first to search the internet for “water quality report” along with your city/municipality name, as most of these are available online.  If you want to do your own tests to check out what is coming out of your tap, there are some affordable options out there without having to mail a sample away to a lab.  First, your local fish store will most likely sell a test kit for under $30 that will test for ammonia, nitrite, nitrate, and pH – sometimes even hardness (GH and KH).  These are titration kits, which means that you will be handling some dangerous chemicals so I urge you to use caution, keep them out of the hands of children, and wash up well after handling.  The funny thing is that I have yet to find an aquarium store that sells chlorine tests – for this you will need to do some digging online or find a pool supply store that will sell you a DPD test kit for both free and total chlorine.  I wound up finding a test kit from an online chemical company that cost me about $18 for 50 tests – the nice thing about these as you saw is that they are litmus-style strips which means I don’t have to handle or store any toxic chemicals.  Some pool supply companies will sell test kits that include a battery of tests like the ones sold at fish stores, so shop around for the best deal in your area.  There are also “well water test kits” available online that most likely work the same way.

That’s about it for my thoughts on water for now.  Hopefully you enjoyed learning along with me and have started to think about the importance of water quality as it relates to supporting living ecosystems – for whether we are talking about gardening, fishkeeping, farming, or simply the water we drink, it is one of the most fundamental building blocks of health and life that there is!

I will continue to update occasionally on how the ascorbic acid treatment does with the fish tanks over the long term, as I continue to learn and work towards an aquaponic setup.  But for the near future I am going to be planning out my summer garden(s) and working to revamp my indoor greens growing operation, so look for more updates from the homestead soon!

What’s in your water? (part two)

To address the problem of chlorine and other water treatment residuals in our tap water, the marketplace does have a few solutions to offer. One of the first things you will hear from your local hydroponics or aquarium store is “Reverse Osmosis!”

This method of filtration is one of the most thorough methods out there, perhaps second only to distillation for its effectiveness. This comes with several downsides, however. First, the unit itself can range from a couple of hundred dollars to over a thousand just for the parts. These units can quickly become a DIYers nightmare as they are usually made of plastic and replacement parts are hard to come by if you went the cheap route – and a professional install costs even more. Additionally these come with 3 to 5 stage filters, and each one of those must be replaced on an annual basis, adding to the expense.  Thirdly, in order for the unit to produce just 5 gallons of usable water, it has to flush over 25 gallons of waste water down the drain – to me this is unacceptably wasteful, especially considering all the steps that water had to go through just to get to my tap.  And finally, the real kicker for me, is that the RO process actually acidifies the water, dropping it down in most cases to a pH of 6 or lower.  This means that one must then add materials back into the water to make it a neutral pH so that it is safe to drink long term, to feed to your plants, to add to a fish tank.  For these reasons I’ve decided that for my needs RO water doesn’t make sense.

What about other filtration methods?  Well there are whole house filters on the market right now that are actually very good.  These are usually multi-stage units that don’t have the RO problem of having to dump waste water, and some of the filter elements are made to last several years.  But again, these aren’t cheap, and I need a solution that I can use in my tanks today!  Most of the shower filters, which you may be tempted to attach to your garden hose, are only capable of dealing with free chlorine – not chloramines – so I’ve ruled those out as well.  What we are currently using for our drinking water is a simple pitcher-type charcoal drip filter, which gives us a better tasting water and some peace of mind knowing that at least some of the chemicals in our tap are being filtered out.  The trick with these is to change the filters often – as once they’ve reached capacity on what they can take out of the water, some of those chemicals will start leaching back into the pitcher and your drinking water will actually contain more than from the tap!  These filters add up over time, but are such a small initial investment that it makes sense to use them for our drinking water.  My fish tanks however range from 5 gallons to 30 gallons right now, with some small planter vases scattered around the house, meaning I currently have over 100 gallons of fish tanks in our home – so I need a means of treating a larger quantity of water than our little pitcher filter can handle!  And it turns out that they’re not removing all the chloramine anyway.

It used to be that when you were setting up or doing a water change on a fish tank, you would just fill up your 5 gallon buckets and let them sit out, or “age”, for a day or two.  This would effectively remove all of the chlorine in your tap water because at that time the municipalities were using “free” chlorine – just like the stuff out of the bleach bottle.  This form of chlorine is volatile enough that it will simply evaporate out of the water over time.  The game changed when municipalities found that they could get a longer shelf-life for their treated water by using the more stable chloramines, which don’t evaporate and can’t be boiled out.  (Chloramines are actually chlorine bound with ammonia.)  This meant that on the consumer end we’ve had to turn to commercial water conditioners in order for our fish tank to survive a simple water change.

Long exposure charcoal filtration is an option I toyed with early on, but not having a cheap source of clean charcoal handy, and considering the waste it generates, I decided to keep searching.

Those of you who have brewed your own beer or made your own wine will know about potassium/sodium metabisulfite – or Campden tablets.  These are used for two things – removing chloramines for brew water to result in better tasting beer, and killing wild yeasts and bacteria to control fermentation.  This initially sounded like a possible way to take the tricky chloramine molecules out of the picture, but then I remembered that sulfites are added to kill small organisms that could result in spoilage of the beer/wine.  And in the fish tank, we need those organisms to process our fish waste so the fish don’t drown in their own excrement!

So this search was getting long and frustrating, but I knew that someone out there had to be doing aquaponics in an urban setting on a hobby level or larger without spending huge amounts of money per gallon of water.  And then I came across the idea for neutralizing chloramines with Ascorbic Acid.  That’s right, good old Vitamin C!  It turns out that people using home kidney dialysis machines have been using ascorbic acid to neutralize chloramines in tap water for as long as they’ve been used in water treatment.  Because chloramine is chlorine bound with ammonia, there is a small amount of ammonia released into the water which the biological filter, or nitrogen cycle, has to deal with.  The chlorine, when unbound from the ammonia, is now free to evaporate out of the water before it is added to a living tank – this process takes only a couple of hours.  As long as the treated water is added slowly to an existing tank the ammonia should not adversely effect the livestock present.  The only other by-product is dehydroascorbic acid, which is a form of vitamin C which is a nutrient of great benefit to organic life, and will actually increase the fish’s immunity to disease – just like it does for us humans!

If you’ve noticed, we’re adding an acid to our tap water, which is going to have an effect on the pH level of that water, so that is something we’ll have to monitor when testing if this actually works as claimed!  The reality is that the dose is small, about 1.7 grams per 22 gallons of water, or less than 400mg for a 5 gallon bucket.  Therefore our net effect on the pH level should not be extreme, and as a bonus my tap water is fairly alkaline – around 8.0 pH last time I took a sample – so a small downwards swing might actually be a good thing in my case.

In part three of “What’s in your water?” I will walk you through my real-world testing of ascorbic acid as a water conditioner, and give you some ideas on how to test your water – because knowledge is power.


What’s in your water? (part one)

I’ve been keeping freshwater fish since early 2011. My philosophy has been to keep things simple and to let nature teach me what works, so that I can invest as little as possible in time and money to make healthy ecosystems on a small scale.  The goal initially, as with most aquarium hobbyists, was to have a bit of life inside our home – to give us something to look at and engage with, other than a screen.


As time has gone on, I’ve learned that all this is easily achieved by imitating and fostering nature.  In an aquarium, this means a healthy nitrogen cycle (I always establish this through fishless cycling), a large quantity of live plants (see the Walstad method), biodiveristy, and most importantly – good water!

As I’ve rediscovered my interest in growing my own food, the lessons I’ve learned from fishkeeping have started to reappear in new and interesting ways.  It turns out the nitrogen cycle doesn’t just occur in my little hobby fish tanks, but absolutely everywhere in nature – including the soil we grow our greens in!


So here’s the problem.  I live in a densely populated urban area with only the water from my tap to work with (no water catchment options yet).  Why is that a problem?  Well, the municipality I live in has to provide safe clean drinking water to a lot of people, and the way they do that is by treating it, among other things, with chlorine – actually, chloramines.  And these compounds that keep the water free of dangerous pathogens and bacteria, when introduced to a healthy aquarium with fish in it, destroys the good bacteria (see nitrogen cycle) and kills the fish!

So what happens when I use that same tap water to keep my indoor herbs and greens growing strong?  What happens to the beneficial microbes and nitrifying bacteria in my growing medium or soil?  I’m not suggesting you don’t water your plants from the tap – but you really should know what is in your water, so that you can give your soil and your plants the best conditions to thrive.  Fortunately the EPA has mandated that municipalities provide their residents with an annual water quality report, which you should be able to find very quickly through a web search.


Obviously I’ve had to treat the water I use for my fish tanks.  To do so up to this point I’ve been using an expensive, commercial aquarium water conditioner, which has done a flawless job of making that same tap water safe for fish.  But there’s a catch – it says right on the bottle “not for human consumption.”  So there’s no way I’m drinking water out of my tank (not that I would really want to), eating the fish I raise in the water, or feeding the nutrient rich waste water to the greens I am growing to feed my family.  In fact, these water conditioners contain (or have as by-products) toxic hydrosulfites and even formaldehyde.

So, if I want to keep fish more naturally, use their waste water to feed my plants, and even (hopefully soon) get myself experimenting with aquaponics, I really need to find a cost effective way to treat my water.

…and I think I’ve found it!  Stay tuned.