Need a bit of help.

3549 Views 17 Replies 9 Participants Last post by Error, Jun 30, 2004

Error

Discussion Starter · Jun 26, 2004

These are my tank specs:

46 gallon bowfront
5.5wpg PC 10000K and 6700K
Soil underlayer below gravel

Fertilator says I'm adding (three times weekly):
N 12.7 (KNO3)
P 3.85 (Monobasic P sulfate)
Plus 5ml Flourish
Traces via CSM + B
I am also adding Kent Botanica Grow for Mg and Ca
CaCl for signs of a Ca deficiency that still persist
Moderate/heavy fishload

Pressurized CO2, between 10 and 25ppm depending on the time of day

The problem is that the plants are still not growing as well as I'd like. They do not get bushy, and they grow slowly. The Broadleaf stellata I ordered a month ago is in a well-lit location but has only developed two nodes with submersed foliage and appears to have stopped altogether. There is no algae to speak of other than the green spot that develops every few weeks on the glass.

Leaves of Hygrophila polysperma, Ludwigia glandulosa and Ammania senegalensis are still curling and stunting. Ludwigia inclinata will steadily lose its lower leaves until it develops floating shoots, and only these retain their leaves.

Am I adding too many ferts here? (I started to suspect it today, when the water got cloudy after my daily dose). Is too much P limiting N? I'm no biochemist

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Steve Pituch

· #2 · Jun 26, 2004

Error,
Have you ever successfully tried a tank with 5.5 W/g? I would think your nutrient usage could be quadruple that needed at 2 to 3 W/g. As much as I like to use the Estimative Index, I think you will need to do daily lengthy chemical analyses with expensive test kits until you get the dosing right. At that much light I think the balance of the tank is a very fine line and very hard to do. From what I have seen of your work, you are more successful than I am (have better results). Perhap I can learn something from you, but I will be impressed if you can keep the tank in good shape at that light level.

Good luck, and please let us know how things work out. What I would do is gradually lessen the light until you are not able to detect deficiencies.

Normally we measure nitrate in ppm and grams of KNO3. What does the 12.7 measure?

Regards,
Steve Pituch

Error

Discussion Starter · #3 · Jun 26, 2004

The 12.7 is ppm.

The reason why I've got so much light now is because I've been trying to get a high-light tank right for some time. I wonder if the problem is not somehow related to the soil substrate?

As far as adding quadruple the amounts needed in other tanks, I am adding a full half teaspoon of KNO3 three times weekly. That's a lot of N.

Ben Belton

· #4 · Jun 27, 2004

I usually keep 5+ watt/gallon tanks. I have found that the secret is making sure you have 30ppm CO2 and many many times the amount of traces and Fe recommended on the bottles.

In my 40 breeder with 5.7 watts/gal I often put in 15 ml of Flourish and 15ml Flourish Fe 2-3 times weekly.

Steve Pituch

· #5 · Jun 27, 2004

Error,
I don't think that the soil substrate will hurt. Sometimes if the soil is too hot in the beginning you will get algae blooms but you don't seem to have that problem. In my experience up to 3.5 W/G it doesn't hurt in any way.

OK, I confirmed the 12.7 ppm NO3. But I put 10 ppm NO3 in a 2 W/G tank twice per week, so your 12.7 three times a week is not too much more. True, I don't measure No3 since I don't have an expensive test kit and I do 50% water changes per the Estimative Index, but you aren't dosing much no3 in my opinion. You might want to double the no3 dose if you do 50% water changes and see what happens. Do you have a Lamotte or Hach no3 kit? If not try to double the dose and do the 50% weekly water change.

Hi light also means 3.5 W/g. You should really get the tank stable at 3 or 3.5 W/g first before trying to run the tank on Amphetamines (>3 W/g). :lol:

Steve

cS

· #6 · Jun 27, 2004

I doubt that your macros are deficient. If I remember correctly, the maximum uptake of N per day is 3-5 ppm. Your fish load and KNO3 input should be ample.

What is your tap water GH, along with individual Ca and Mg concentrations if available? What is your CaCl2 dosing regiment (quantity and frequency)?

Also, why is your CO2 fluctuating so much between 10-25 ppm? Do you have it off at night? Nonetheless, like Ben suggested, I would amp it up more consistently around 30 ppm.

Error

Discussion Starter · #7 · Jun 27, 2004

Tap GH is 10.

CO2 is indeed off at night, I will turn it back on. I also am using a Whisper overflow-style filter, I imagine that prevents the CO2 from getting too high.

CaCl dosing is 1 tsp daily. In my tank that translates into about 1 ppm daily, at least according to fertilator. Also, when I add this, it clouds the water substantially and for almost the entire day. This leads me to believe that there's plenty of Ca in the water (don't know if that's true) and that the problem lies elsewhere.

I do not dose Mg whatsoever, and I have no value for its tapwater concentration in my area.

The tank gets 50-75% weekly water changes.

dennis

· #8 · Jun 27, 2004

Calcium in forms not specific for aquariums (like turbo calcui) seem to be of a larger grain size and take a long time to dissolve, it also has something to do I believe with the chemistry of how things dissolve as to why it clouds your water. I would not assume that the cloudiness is a result of creating a "super enriched" solution with the CaCl. Youmight try using a different form, or putting the CaCl in your filter to dissolve slowly over hte course of the day. Its possible that Mg is actually the culprite. I would try dosing some Epsom salts and see whet that does after a week or 2. SOrry I cant say how much to dose but I just read a post, by Tom Barr it think, advising this and an amount was recommended. Definately, I would try to maintain my CO2 at 30ppm or so

Whenever I get flucuating CO2 I start having problems.

Hope that helps

Edward

· #9 · Jun 27, 2004

Error,

plants need Ca : Mg in a ratio of 3 : 1 to 4 : 1.
You can get a test kit for Ca by Nutrafin Hagen that will help you to determine Ca and Mg concentrations.

First you measure GH and Ca, then calculate the rest, example:

GH 10 degree
Ca2++ 2 degree
--------------------------------------------------------------------------------
Ca2++ [ppm] = 20 x Ca2++ [degree]

40 = 20 x 2

Ca2++ 40 ppm
--------------------------------------------------------------------------------
Mg2++ [ppm] = (( 20 x GH [degree]) - ( 50 x Ca2++ [degree])) / 4.1

24.4 = (( 20 x 10 ) - ( 50 x 2 )) / 4.1

Mg2++ 24.4 ppm
--------------------------------------------------------------------------------
Ca 40.0 ppm
Mg 24.4 ppm

The tap water should be measured first and then going from that point on will lead you to more successful result.
I have grown plants for years in Ca of 10 to 20 ppm and never seen any deficiency. Large doses of CaCl2 cause contamination, chloride that fish don't feel happy about.

Edward

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Jeff Kropp

· #10 · Jun 27, 2004

Error said:
Fertilator says I'm adding (three times weekly):
N 12.7 (ppm) (KNO3)
P 3.85 (ppm) (Monobasic P sulfate)

I think that addressing hardness factors is too far down the troubleshooting line for you. Consider this trouble shooting order: Light, C, N, P, K, Ca, Mg, Fe, then other micros.

You might take a look at your ratio of N to P. Currently your N/P ratio is 3.3. I have had trouble with low ratios causing N limitation when my frequency of supplementation outpaces the natural N production rates in my tank. My current lean supplementation uses a N/P ratio of 8.25, every other day, at 3 wpg. Tom Barr's estimative index recomends an N/P ratio of 10 based on a compositional dry weight analysis of aquatic vegetation.

Excess soluble P accelerates Fe reduction as does excess light.

Losing older leaves is often considered symptomatic of C and K shortfalls.

With a soil substrate, or an old and very mulmy substrate, you need to maintain good plant health. If a plant's respiration is too weak to maintain healthy roots in a strongly reductive substrate you will have trouble getting soil bound nutrients up into your plants.
___
Jeff

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Roger Miller

· #11 · Jun 27, 2004

The cloudiness from adding CaCl2 is caused because the calcium you add reacts with the bicarbonate (KH) in your tank and produces CaCO3. The cloudiness goes away when the CaCO3 settles out or (more likely) redissolves. Redissolving the CaCO3 requires CO2.

I think you have gone *way* overboard on trying to fix a calcium problem that you probably don't have. If you have 10 dGH in your tap water then I think it's highly unlikely that any part of your problem has to do with a calcium deficiency.

I've never kept a tank with that much artificial light, so I won't offer much more. As near as I can tell a watt per gallon measure over 5 on a medium-sized or large tank creates far more problems than it solves.

Roger Miller

Error

Discussion Starter · #12 · Jun 27, 2004

Roger Miller said:
As near as I can tell a watt per gallon measure over 5 on a medium-sized or large tank creates far more problems than it solves.

That's the idea behind this. I'd like to determine just how to do a high light tank correctly. I have done tanks in the range of 1-3 with success. I am trying something new.

Alright, here is the dosing regimen I am going to begin on Monday (water change day):

Days 1, 3, 5, 7: .5 tsp. KNO3 (approx. 12.7ppm), 1/16 tsp. Monobasic K Phos (approx 1.6ppm)

Days 2,4,6: 1/2 tsp CSM + B.

I'll eliminate the Flourish, Kent Botanica, CaCl, etc.

I have also taken the CO2 off the light timer. We will see what happens. If I need to up the N (which I doubt, given my fish load), then I will.

Suggestions welcome.

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Roger Miller

· #13 · Jun 28, 2004

Were I to write

"As near as I can tell hitting yourself on the head with a mallet causes more problems than it solves."

And someone were to reply

"That's the idea behind this. I'd like to determine just how to hit myself on the head with a mallet correctly."

I would have to worry.

What do you expect to do with 5.5 watts/gallon that you can't do with less?

Roger MIller

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Error

Discussion Starter · #14 · Jun 28, 2004

LOL

Well, I may be hitting myself with a mallet, but the idea behind it all is I'm too cheap to let this 192 watt PC fixture go to waste

gnome

· #15 · Jun 28, 2004

If it were me with this dilemma, I might use it as an excuse to buy a bigger tank :lol:!

That should solve most of your problems :lol: .

-Naomi

cS

· #16 · Jun 29, 2004

Error said:
Tap GH is 10.

:shock: Hehehe. And here I was thinking that you're somewhere nearer to 1 dGH.

CaCl dosing is 1 tsp daily. In my tank that translates into about 1 ppm daily, at least according to fertilator. Also, when I add this, it clouds the water substantially and for almost the entire day. This leads me to believe that there's plenty of Ca in the water (don't know if that's true) and that the problem lies elsewhere.

The addition of only 1 ppm Ca per day SHOULD NOT make the tank cloudy for almost an entire day! If your CO2 is adequate then the CaCO3 should dissolve within a couple of hours (less in your case of only 1 ppm Ca). Do let us know how your tank fare with the new 24/7 CO2 schedule.

P.S. I definitely agree with Naomi - go big. :mrgreen:

Roger Miller

· #17 · Jun 30, 2004

Error, how much calcium were you dosing to get 1 ppm?

Cs' comment about dissolving 1 ppm of calcium is right and got me thinking about it. I posted a comment to the Fertilator bug forum.

Roger Miller

Error

Discussion Starter · #18 · Jun 30, 2004

You know, the first time I ever checked my Ca with the fertilator, I thought the value might have been a tad skewed. 1 TEASPOON a day gives 1ppm? Never seemed right, but I never though to bring it up.

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