I've recently setup a 600 liter heavily plated tank which has been running for about 6 months. After battling algae for most of that time it seems I've got a grip after reducing the use of my locally available aquarium plant fertilizer(Sera) and using a terrestial NPK fertilizer containing trace elements (Scotts 14-7-14). I don't have easy access to some of the components of PMDD at my remote location.
Growth rate is fine but I have noticed that the leaves of some stem plants are beginning to show brown speckling and I'm not sure if this is due to a nutrient deficiency or disease. The spots only appear on the lower, older leaves. The condition was at first only noted on the three species of HYGROPHILA CORYMBOSA in the tank so I thought that this was the pattern of which older leaves deteriorated on that group, but now the same speckling is beginning to appear on the Watersprite which is ordinarily bullet proof.
I'm wondering whether the Scotts fertilizer contains some component that the plants find disagreeable. The fish seem unaffected. Typical values are as follows:
PO4 1.0 PPM
NO3 10 PPM
Fe 0.1 PPM
CO2 25 PPM
Lighting: 440 watts Compact T5 VHO
Temperature 28 Deg C.
The tank is lightly stocked and 25% water changes are conducted weekly, along with trimming.
Any ideas on the cause of theses spots?
Cheers,
Brown Spots on Leaves
-
SCMurphy
- Site Admin
- Posts: 2104
- Joined: Sun Nov 23, 2003 1:40 pm
- Real Name: Sean
- Location: Maryland United States
Ok, don't mind the conversion it is for a non-metric crowd, 158 gallons with 440 watts of light should be good levels for that size tank. Nutrient ratios look good. Do you know if the Scotts fert has micro nutrients? What substrate are you using?
This is what I would do if it were my tank and I were seeing what I think you are seeing.
Now that the tank is stable I would try doing alternate weeks of the fertilizers, if the algae came back after a Sera week I would do two weeks of the Scotts and then a week of the Sera. I think that the Scotts is missing some things that are needed in an aquarium that Scotts expects to be available from the soil that terrestrial plants are grown in. I think that the Sera is short on the N-P-K side someplace (which contributed to the algae) and the plants are using up the Scotts without getting enough micros and so are canabalizing their old leaves.
<edited><editID>SCMurphy</editID><editDate>38154.2989930556</editDate></edited>
This is what I would do if it were my tank and I were seeing what I think you are seeing.
Now that the tank is stable I would try doing alternate weeks of the fertilizers, if the algae came back after a Sera week I would do two weeks of the Scotts and then a week of the Sera. I think that the Scotts is missing some things that are needed in an aquarium that Scotts expects to be available from the soil that terrestrial plants are grown in. I think that the Sera is short on the N-P-K side someplace (which contributed to the algae) and the plants are using up the Scotts without getting enough micros and so are canabalizing their old leaves.
<edited><editID>SCMurphy</editID><editDate>38154.2989930556</editDate></edited>
"したくさ" Sean
Aquascape? I'm a crypt farmer.
If you've got bait, I've got wasabi!
I wish I could be like Mr. Sarcastic when I grow up!
Aquascape? I'm a crypt farmer.
If you've got bait, I've got wasabi!
I wish I could be like Mr. Sarcastic when I grow up!
Sorry about the metric, yes 150+ gallons converted. I looked closely at the packaging on the Scotts and I found the following data other than the obvious NPK percercentages:
14.0% Calcium
0.01% Boron
0.002% Copper
0.15% Iron
0.001% Manganese
0.001% Molybdinum
0.003% Zinc
As a comparison I checked the contents on the Sera bottle and saw the following data:
0.89% Ferric chloride
0.83% ethylene diamine tetracetate [have absolutely no idea]
0.004% manganous chloride
0.002% magnesium chloride
0.0002% boric acid
0.00016% suphuric acid [probably as a preservative]
About the only thing you could say is missing from the Scotts is the chloride and whatever mystery component is in the tetracetate but I failed to mention earlier that I use RO water which is then doctored only with Sera mineral salts, never with tap. The package shows various concentrations of Sodium, Potassium, magnesium, calcium, chloride, bicarbonate and sulfate, so really I should be covered by the combination of the mineral salts and the Scotts which in fact has zinc and copper which the Sera lacks. I confirmed that the Sera has no NPK.
One mystery is that we assume that the trace elements and minerals are consumed at an equal rate as the measurable components such as phospate, nitrate and iron but maybe this is an incorrect assumption. I noted that ther are patassium and magnesium test kits for marine water. has anyone ever thought about how to use these test kits for fresh water , maybe by adding some sodium chloride?
I will try your scheme although I think I can guess the results - algae. I obseved that if I do not add the Scotts every thee days or so I develop a grey surface film which very quickly turns to green scum. It appears as if the tank is macro, not micro nutrient limited so I was thinking along the lines that maybe the Scotts has TOO much of something, maybe copper or zinc? I've noted that the Hygrophilas actually drop their affected leaves. Then as the leaves drift you can see holes where the small speckled spots were. The lower third of these plants have all lost their leaves. I can see similar speckling on the oldest leaves of the large broad leaf swords. These brown speckles then develop a yellow ring and the yellowing grows. These patterns don't seem to match anything I've seen on the various nutrient deficiency charts.
I've almost decided to give up on Sera fertilizer, it's very expensive dosing this size tank. Unfortunately they have a monopoloy in my area and that's why I've resorted to experimenting with terrestial fertilizers.
Cheers,
14.0% Calcium
0.01% Boron
0.002% Copper
0.15% Iron
0.001% Manganese
0.001% Molybdinum
0.003% Zinc
As a comparison I checked the contents on the Sera bottle and saw the following data:
0.89% Ferric chloride
0.83% ethylene diamine tetracetate [have absolutely no idea]
0.004% manganous chloride
0.002% magnesium chloride
0.0002% boric acid
0.00016% suphuric acid [probably as a preservative]
About the only thing you could say is missing from the Scotts is the chloride and whatever mystery component is in the tetracetate but I failed to mention earlier that I use RO water which is then doctored only with Sera mineral salts, never with tap. The package shows various concentrations of Sodium, Potassium, magnesium, calcium, chloride, bicarbonate and sulfate, so really I should be covered by the combination of the mineral salts and the Scotts which in fact has zinc and copper which the Sera lacks. I confirmed that the Sera has no NPK.
One mystery is that we assume that the trace elements and minerals are consumed at an equal rate as the measurable components such as phospate, nitrate and iron but maybe this is an incorrect assumption. I noted that ther are patassium and magnesium test kits for marine water. has anyone ever thought about how to use these test kits for fresh water , maybe by adding some sodium chloride?
I will try your scheme although I think I can guess the results - algae. I obseved that if I do not add the Scotts every thee days or so I develop a grey surface film which very quickly turns to green scum. It appears as if the tank is macro, not micro nutrient limited so I was thinking along the lines that maybe the Scotts has TOO much of something, maybe copper or zinc? I've noted that the Hygrophilas actually drop their affected leaves. Then as the leaves drift you can see holes where the small speckled spots were. The lower third of these plants have all lost their leaves. I can see similar speckling on the oldest leaves of the large broad leaf swords. These brown speckles then develop a yellow ring and the yellowing grows. These patterns don't seem to match anything I've seen on the various nutrient deficiency charts.
I've almost decided to give up on Sera fertilizer, it's very expensive dosing this size tank. Unfortunately they have a monopoloy in my area and that's why I've resorted to experimenting with terrestial fertilizers.
Cheers,
These are the VHO T5 compact bulbs. Do you know the ones I mean? The double barrel type with 4 pins. Half of them are 3 months old and the other half are less than a month old. I started the tank off as "Low Tech" primarily because I was forced to use the pathetically dim lights that came with the hood (50 watts of Gro-Lux and 50 watts of Cool White). Ironically, for the first three months of operation I had absolutely zero algae using these sad bulbs. I then mail ordered and retrofitted the T5's and thats when tall my algae trouble started.
The 1 month old bulbs are there because of there spectral qualities. The T5 bulbs I installed originally are marketed as plant specific but they have an eerie purplish cast which I found depressing. I changed out half of them when the Osram "Daylight" bulbs became available. Tremendous difference to the human eye but I feel that the plants appreciate it as well. Glossostigma Elantoides, which I find difficult and unforgiving, was on the brink before I installed the new Daylights and now the small patch directly under the Daylights has already spead out to doubled the area in a month.
Cheers,
The 1 month old bulbs are there because of there spectral qualities. The T5 bulbs I installed originally are marketed as plant specific but they have an eerie purplish cast which I found depressing. I changed out half of them when the Osram "Daylight" bulbs became available. Tremendous difference to the human eye but I feel that the plants appreciate it as well. Glossostigma Elantoides, which I find difficult and unforgiving, was on the brink before I installed the new Daylights and now the small patch directly under the Daylights has already spead out to doubled the area in a month.
Cheers,
I Know...we might have to take a ourse in metaphysics to figure this one out...
The substrate is a German product marketed here by the name "Aqualit" I have no idea what the American equivalent would be but I thibk it is clay based and it is very porous. The only description of it I've ever been able to uncover is at the manufacturer's website at:
<a href="http://www.hobby-dohse.de/aqua_e/index.php" target="_blank">http://www.hobby-dohse.de/aqua_e/index.php</a>
I've got about 20 Kilograms of it and I supplement with Sera root tabs every month or so. Lets see...what else.. The pH measured when the lights go on is about 6.75 as measure by a Hanna pocket meter. CO2 is injected 24/7 with an in-tank diffuser. Typical TDS is 175 ppm or just under 380 usiemens. With the TDS measurement I've stopped testing gH. kH varies from about 4 to 7 German degrees depending on the mineral salt addition.
Filtration is via two internal sumps mounted at opposite ends, each fitted with a 750 liter per hour submersible. obviously no carbon, just sponges and Eheim SUBSTRATpro media. Gravel gets only a superficial vacuuming occasionally just for appearances sake.
I do have quite a bit of African driftwood which took ages of water changes to clear the tea color. The Hygrophila's are planted right next to the driftwood. Could the tannins leached into the gravel from the wood have been absorbed and havd had some effect? Who knows what nasties are in the wood? Then again I have ALTERNATHERA REINECKII "ROSEAFOLIA" planted right next to the wood as well and that grows to the point where it is garishly magenta and is almost overwhelming.
It could still be that the Hygrophilas are more suceptible. Of all the plants in the tank they have the most radically different change in appearance. They look nothing like the did when initially planted. They came from Tropica in Denmark and I know they were raised emersed as were all the others. The submersed leaf form change is amazing.
Any thoughts on the driftwood contamination theory?
Cheers,
The substrate is a German product marketed here by the name "Aqualit" I have no idea what the American equivalent would be but I thibk it is clay based and it is very porous. The only description of it I've ever been able to uncover is at the manufacturer's website at:
<a href="http://www.hobby-dohse.de/aqua_e/index.php" target="_blank">http://www.hobby-dohse.de/aqua_e/index.php</a>
I've got about 20 Kilograms of it and I supplement with Sera root tabs every month or so. Lets see...what else.. The pH measured when the lights go on is about 6.75 as measure by a Hanna pocket meter. CO2 is injected 24/7 with an in-tank diffuser. Typical TDS is 175 ppm or just under 380 usiemens. With the TDS measurement I've stopped testing gH. kH varies from about 4 to 7 German degrees depending on the mineral salt addition.
Filtration is via two internal sumps mounted at opposite ends, each fitted with a 750 liter per hour submersible. obviously no carbon, just sponges and Eheim SUBSTRATpro media. Gravel gets only a superficial vacuuming occasionally just for appearances sake.
I do have quite a bit of African driftwood which took ages of water changes to clear the tea color. The Hygrophila's are planted right next to the driftwood. Could the tannins leached into the gravel from the wood have been absorbed and havd had some effect? Who knows what nasties are in the wood? Then again I have ALTERNATHERA REINECKII "ROSEAFOLIA" planted right next to the wood as well and that grows to the point where it is garishly magenta and is almost overwhelming.
It could still be that the Hygrophilas are more suceptible. Of all the plants in the tank they have the most radically different change in appearance. They look nothing like the did when initially planted. They came from Tropica in Denmark and I know they were raised emersed as were all the others. The submersed leaf form change is amazing.
Any thoughts on the driftwood contamination theory?
Cheers,
