Hydroponic Nutrient for planted tank

Got a kg of chemicult from a garden shop this afternoon ..
Wonder if anybody has tried / is using this in a planted tank?

Macro -
6.5% N
2.7% P
13.0% K
7.0% Ca
2.2% Mg
7.5% S

Micro -
.15% Fe
0.024% Mn
0.024% B
0.005% Zn
0.002% Cu
0.001% Mo

I could only find one reference to this stuff and an aquarium - a guy that had a beautiful 50G and he was dosing "half a teaspoon every second day or so, with 30% water changes weekly."

I get the feeling that the Micro is a bit low - but I can always add some Trelmix to the math.

I think my bigest concern is the amount of Cu I am adding the system - but big water changes should sort that.

Or maybe this make me an algae grower :noworry:

 

copper never gets removed from a tank period....no matter how many water changes you do....if you use that stuff, that tank will never be a successful marine tank if you go that route. good luck

 

Dear f-fish,

Nutrient mixes of this nature are not suitable for feeding aquatic plants in an aquarium because a major portion of the nitrogen is in ammonia form which is highly toxic to your fishes, the rest in is in nitrate form and although not so toxic to the fishes is also detrimental. The phosphate is also far too high and will lead to algal growth and the Potassium is too high. The Sulphur is most probably in sulphate form and should not be used in an aquarium. Your concerns about the Copper are unnecessary as the levels of copper are very low.

However, you should not even consider using these type of mixtures and you should only use aquatic fertilizers.

Kind regards,

Dirk

 

Thanks for the reply Dirk ... I shall not be adding this to any tanks that have fish in them.

I am playing with some KNO3, MgSO4 and looking to get my paws on some KH2PO4 - will stop at the hydroponics shop tomorrow. For micro's I am using trelmix a trace element solution. Still trying to find a good recipe for my tanks - at the moment it is a discovery process.

The goal is to 1) setup a repeatable hydroponic / aeroponic system for aquatic plant cultivation 2) Learn to "read" a tank's symptoms and knowing how to fix it. 3) Not be reliant on a LFS product that is imported for maintain my tanks.

 

I would like to start with something like this ...


But If I replace the Sulfate with a CO3 then I dolomite looks mighty good to use - expect that it does not dissolve ...

Maybe I should start by getting my tap water tested - to see what I have in that.

 

Hi f-fish,

Again a few comments:

What is critical in developing a fertilizer mix is that all of the components that the plants require are present in correct ratios and amounts. This is something that is just about impossible unless you have extensive chemical knowledge.

With regard to your proposed additives:

You cannot use KNO3 directly because the balance between K and NO3 is not optimal.

You should not use K2HPO4 without KH2PO4 because you will push up the pH too far.

You cannot use the carbonates of the K and Ca as you will push up the carbonate hardness too far.

Trelmix does not contain an optimal ratio of all the trace elements as needed in an aquatic environment.

And so it continues.....

I have formulated my own aquatic fertilizer here in SA which is already used by many, many of the aquarists on this and other forums. Send me a PM for details if you may be interested.

Kind regards,

Dirk

 

Hi Prof Dirk

I am one of the users of your aquatic fertilizer mix. I am aware of the fact that you are not keen to publish the details around the contents. Which I totally understand.

What you have been saying is that it contains no nitrates or phosphates, as fish and fish food provide these.

It is believed that there should be a 10:1:25 ratio between NPK. So we are relying on fish waste and fish food to provide, for example a 10:1 ratio between nitrates and phosphate. Now it has been shown that an imbalance between nitrates and phosphates is the main cause of most green algae. If I were to measure phosphates and discover, for example, 2ppm, but my nitrates are only 10ppm, then I have an imbalance. How shall I supplement the nitrate then, as I would need 20ppm to create the required balance? Or is this balance not really important?

Note that I have quite a low fish load and probably never reach high levels of NO3. But I have a large plant load, so I am wondering if I need more NO3 than what the fish produce, as I have the occasional algae issue...

Perhaps my question is really: if I discover that I need to supplement one or more chemicals, what would you recommend I do?

Regards
Lauré

 

Hi Lauré,

I have done extensive reading up and web surfing on the approaches used by the persons who show these tanks that look like perfect gardens. Basically the water in their tanks is a strong solution of fertilizers which is also strictly speaking unsuitable for fishkeeping. It is also in systems such as these where you use such high levels of nutrients that you have such algal problems and I believe that when using these high nutrient levels that an imbalance as you mention becomes a trigger for algae.

I have a fundamental problem with the use of such high nutrient levels. For me it is in direct conflict with the keeping of sensitive fishes, which is my speciality. In nature, rivers or lakes that are covered with algae, are polluted with high levels of phosphate and nitrate, and are unsuitable for the survival of senstive fishes. Natural water systems have only extremely low levels of these nutrients and have no algal growth. My fertilizer mix is aimed at creating good plant growth conditions at lower levels of plant nutrients whilst still allowing you to keep fishes. When using these lower levels of nutrients, my experience is that the nitrate and phosphate levels as supplied by the fish waste are adequate and do not create a problem.

Kind regards,

Dirk

 

Thanks Dirk ... things are staring to make sense i.e. why you do what you do and why it differs from the "show" mixes - fish (and probably plenty of them). I crawled over to the LFS yesterday - had a look at the fertz on the shelf and the one had some content listed. As its main components had MgSO4 and K2SO4 - I found this rather odd since you said "The Sulphur is most probably in sulphate form and should not be used in an aquarium." or is this OK to have Sulfates in the aquarium?

Also got the "Sera guide" and they to do not add nitrate and phosphate substances.

 

Hi Prof Dirk

I would agree that keeping sensitive fish like discus in a high light planted tank with demanding plant species that require lots of nutrients is not a long term sustainable situation. I have often wondered if these fancy aquascapes, even those with discus, can be kept up for more than a few months before either the fish or the plants deteriorate.

I have also gone and delved into the history of some threads on the other forum. I have now read some explanations you gave regarding your plant fertilizer. I will pm you the link to the thread if you wish, but it was started by Henk Hugo regarding green spot algae and the argument was around adding PO4 as this algae is caused by an imbalance between NO3 and PO4.

Then slightly off topic - in this same thread I have also read that you use mercury vapour lamps which you equate to about 10 x 40W T8 tubes. So you run a high light setup. I have a question, do you ever get any pearling of the plants? I know you do not feed CO2. I know pearling is caused by oversaturation of O2 due to fast plant growth. I was just wondering if the growth rate with such high light is really fast...

Regards
Lauré

 

Hi f-fish and Lauré,

Firstly, it is not in order to have high sulphate levels in a tank and I do not know why the producers of this product use the sulphate form. Sulphates can cause major problems in a filter if there is too little oxygen circulating through the filter and this could produce byproducts that are toxic to fishes. I have asked some pertinent questions to companies in the past and they often cannot answer because they do not know better, even in Germany or elsewhere where you would expect real experts to be formulating these mixes, so this again does not entirely surprise me, but it is wrong to use sulphates.

Lauré, you will recall that I have stated in other threads that I view keeping sensitive fishes such as discus in an intensively planted and fertilized tank as not feasible. Precisely what you say, in other words that either the fishes or the plants eventually suffer is what I have found. I keep my discus in a large recirculating system completely without plants with a management aimed at discus entirely and not plants. There I can concentrate on conditions which are optimal for my fishes. Remember that the Amazon is largely free of aquatic plants and that so-called "Amazon sword plants" actually occur further south than the Amazon! So, yes, keeping discus and plants are difficult and in conflict in my opinion and in my setup, where I do not have the time to manage both plants and discus all the time.

I remember the thread with Henk and must check what I wrote there.

Yep, my mercury vapour lamps are certainly high light, but not as high as tungsten lamps for example. The tank is also 50 cm deep so the light penetration is accordingly not all that high either. My plants do not pearl O2, but they certainly do grow well. My large sword plants push an average of two leaves per plant per week, which over a period of two weeks can extend to 40-50 cm in length. The tank's dimensions are 185 cm long x 60 cm wide x 50 cm high. I keep some 40 large adult scalare angels in the tank, about ten kribensis and 15 rainbows as well as about 15 apple snails. They get fed heavily with granules, flakes and frozen foods and I do not add any phosphate or nitrates. The tank gets a 40-50% water change at least every two weeks and I then top up with my drops fertilization in other words I add my ferts according to the water I have exchanged. I also now add my Happy Life Happy Carbo as a carbon source instead of CO2, but I have never used CO2.

Hope this gives you a better idea of what I am talking about. Maybe I should post some pics if I have the time...

Kind regards,

Dirk

 

Pictures ... now we're talking ;-) ....

Thanks for sharing .. I like the name Happy Life Happy Carbo - sounds like an Oprah smoothy, best (TM) it.

 

I second that. Sounds like an awesome tank with all the Angels in it...

 

OK, fine I will look into taking some pics again. I have some that I took previously and may post these instead.

Poor old Oprah, now she is sharing Happy Life Carbo products in an aquatic forum....

Kind regards,

Dirk

 

Hi Prof Dirk

So let me summarize what I understand here:
1. Soft water need no CO2 fertilization - this has been discussed at length and I am aware of how and why and agree with the science of it. It is also understood that CO2 fertilization (if done correctly with a ph controller) will undoubtedly improve plant growth.
2. High light is the key to driving plant growth
3. With fast growth comes higher rates of nutrient uptake
4. One then needs to have a decent to high fish load to "feed" the plants.
5. Dirk's drops added as per printed instructions will provide all the rest of the required nutrients
6. Fast plant growth eventually lead to plants outcompeting algae
7. Apple snails are beneficial to break down dead plant matter and possibly also eat some algae. I read that there are 2 types, Pomacea bridgesii and Pomacea canaliculata. The latter will eat plants...so avoid it!
8. Weekly water changes of 40% to 50% will "reset" the tank parameters and is crucial and non negotiable.

I really want to increase my plant growth. They are doing fine, but I think I will get a much more stable tank if the plant growth can be increased. I think I need to make a few changes:
1. Increase my lighting. This is costly either way. I can go with T5 ballasts and bulbs mounted in the hood, or open top with some kind of high intensity discharge lamps (mercury vapour or metal halide). The latter is quite expensive. But I will need pendants with good reflectors. Also expensive. :frown: My tank is only 45cm deep, so perhaps T5 would be fine.
2. Increase my fish load. Any ideas? Maybe you got some nice angels for me? :bigsmile:
3. Get some snails

@f-shish: sorry to hijack your thread, mate.

@admins: feel free to split this thread if you wish

 

No problem - Laure, this is perfect - you have added a good deal of content. And highlighted some thoughts that I would only have discovers way later, if at all.

I think in the end we all have the same goal - good plant growth, no algae and healthy fish. How we do this is up to the individual tanks and keepers. I am so glad that one recipe does not fit all - makes this a true hobby and not a chore

 

Hi Lauré,

Your points 1-6 are perfectly correct.

Point 7: You can use apple snails and also ramshorms. I am not in favour of Madagascan liverbearing snails as they multiply to vast levels in the gravel, you do not know how many you have there until one night, after about an hour of lights off, you happen to come into the lounge and see that there are hundreds of snails in the tank. These add significantly to the biological load of the tank as a result of which I am not in favour of them. Other snails are not as good at eating algae or they don't manage well in softer water (e.g. Neritina snails, they are actually estaurine and require harder and more salty water).

Point 8: You not NOT need the 40-50% water changes if your fish load is low. What you then do is reduce the water changes to get the nitrate and phosphate levels up a little more. The only nutrient that is significantly depleted then is iron and you can then just add an iron only fertilizer say on a weekly basis (I can also supply this!) and do a water change every 3-4 weeks instead. The macronutrients are definitely not depleted in this way and the micronutrients with the exception of iron are not used up so fast, so only iron needs topping up.

If you do less water changes in softer water, you must however watch your pH. Remember I have purposely not formulated my drops to alter kH or pH as a result of which you pH could drop between water changes so you need to adjust this with sodium bicarb if the pH drops too much.

Using this approach you can keep fish and plants and you do not need to keep the plants in a bath of fertilizer either without fishes. An aquarium without fishes would just not be attractive to me.

Kind regards,

Dirk

 

Hi Prof Dirk

Thanks for the response. I also sent you some email...