[beerbunny]

Hi all, I'm a newbie to fishkeeping (about a year) and I've pretty much followed the path described in Chapter XI, section A of 'Ecology of the Planted Aquarium'. Having replaced all my living plants with artificial ones gave me a pretty tank, which is relatively easy to look after (as there are no plants, I've been able to turn my LED lights down enough to eradicate the algae problem.), but it's an unsatisfactory solution to the problem. I've found that the addition of Water Lettuce to the tanks slows down the build-up of NO3 to the point that I now only have to do a water change monthly instead of weekly which I see as a step in the right direction, but I'd like to go further in this direction.

When I came across 'Ecology of the Planted Aquarium', I was interested enough to buy a copy, and, having read the book several times from cover to cover, I've decided to have a go at EI Natural, and I'm about ready to start. However, I have concerns about my tap water. I've tested it as far as possible with a JBL TestLab, and the results I got are as follows:-

KH - 2 deg dKH
pH - 7.5
GH - 4 deg dGH
NH4 - 0.2ppm
NO2 - 0.025ppm
Cu - 0ppm
O2 - 8ppm
NO3 - <0.5ppm
PO4 - 3ppm
SiO2 - 0.8ppm
Fe - <0.02ppm
K - 0ppm
Mg - 6ppm

As a result of the above, I used JBL Aquadur to raise the KH to 7, although some of the readings now seem a bit high, e.g., Mg - >10 (highest reading on the chart), K - >15 (again, highest reading I can get). For some reason, the pH is still 7.5.

My biggest concern is the PO4 level. I can reduce it to zero by using JBL Phosex Rapid, but that tends to leave the water containing too much Fe (up to 1.5ppm, which does gradually decrease over about one week to about 0.1ppm as the Fe compound precipitates out)

My questions are:- Should I be concerned over the level of PO4 and, if so, what should I do about it? Should I be considering RO water? Are there better ways of increasing water hardness than using Aquadur?

Apologies for the length of this post,

Thanks in advance,

John Jones

 

[Michael]

Welcome to APC! For some reason your post was "moderated", meaning that the site robots thought it was suspicious, but I've approved it.

I don't know enough chemistry to answer your question, but be patient and someone else will.

 

[dwalstad]

I was pleased to see that Water Lettuce has reduced the nitrate levels in your tanks. Hurrah for plants!

As to your tap water... I would not worry about the phosphates--or worse--try to remove them by dumping in iron. Phosphates at this level are harmless in aquariums. Rather, I would be more concerned about the soft water.

I looked at the ingredients in JBL Aquadur

https://www.jbl.de/files/faq//393/AquaDur_Web_V01_GB.pdf

It looks okay (i.e., has lots of Ca, less K, and Mg and not too much sulfate). The K and Mg readings are a little high (See my book and Table V-5 on page 85). However, these nutrients are not toxic, and there's plenty of leeway on dosage. Looking at the table and knowing that the commercial product has more Ca than K or Mg, I think you could shoot for a KH lower than 7 and still get the Ca, K, and Mg your plants need. Perhaps a KH of 5 or 6? We're talking here about tinkering...

I would not use RO water. You could add oyster shells to the substrate or the filter, but I think that--if you are so inclined--this product might work fine.

 

[beerbunny]

Thank you both for the replies.

Diana, I'm looking forward to trying the methods described in your book; I hope I have more success than I've had so far with the bright LED lighting and CO2 approach. At the moment, I'm assembling everything that I need, but I hope to have the tank up and running by the weekend (no fish yet, obviously).

With regard to the Aquadur, I was a bit concerned about the Mg figure, so I'm currently trying Aquadur Malawi/Tanganyika, which has a lower Mg content. However, after reading your reply, I think I should maybe have paid more attention to the higher K content. Your suggestion that I aim for a KH of 5 or 6 with the basic Aquadur seems like a good idea (although I'm not really qualified to judge), so I'll give that a try. I'm not sure where I got the idea that KH 7 was a good figure to aim for, anyway. Probably just plucked it out of the air.

So, thanks for your help and wish me luck.

John Jones

PS. Yes, hurrah for plants!

 

[dwalstad]

I would not worry about the K concentration. Despite all the stuff you see on the Internet that implies a magic ratio, there's plenty of leeway with K, Mg, and Ca. If this will make you feel better, I went back to Huebert's 1983 study and he used 16 ppm K, 10 ppm Mg, and 20 ppm Ca in his control media to get good growth and flowering in his aquatic plants. I think your plants would do equally well with any of the AquaDur products used to a final KH of 7 or less OR adding some oyster shells to substrate/filter.

Bottom Line: We don't have to be chemists to grow aquarium plants.

Good Luck!

 

[beerbunny]

Thanks for the advice, Diana, I've done as you suggested and set up my new tank with water with a KH of 5. This brought the the Mg down to 8, although K is still >15. These figures aren't a million miles from the Huebert figures you quoted, so hopefully all should be well.

As you say, we don't need to be chemists to grow aquarium plants, but green fingers would seem to be an asset. Something experience tells me I don't have. However, I'll keep trying.

Thank you again for your help and advice.

John Jones

 

[dwalstad]

As you say, we don't need to be chemists to grow aquarium plants, but green fingers would seem to be an asset. Something experience tells me I don't have. However, I'll keep trying.

As I glance now at my sad houseplants--the Spath shrinking to half its original purchase size, others fading and shedding leaves, a Christmas cactus that never bloomed, few gardeners would dare say I have a green thumb. My aquarium plants do well despite--or perhaps because of--my failings.

Just keep trying.