DPH Tank plant problems and illnesses.
written by: Rob Charite
date: 05 September 2000

Plants can be ill as well and can affect water quality and fish so here's some info on what to do about it.

Damage due to fish or other animals.

Damages due to fish or other creatures are mostly non existent in our hobby.
It is possible that plant lice can affect our plants when the plants are growing emersed.

Fish and snails

They usually won't damage the plants but other fish ( other than discus) can nibble on fine leaves, young sprouts, leave tops and rims, especially the fine leaved plants.
Snails have the ability to "drill" holes in plants with their little "rasp" tongues.
Remedy: Good growing, healthy plants can resist such minor damages.

Maintenance errors and what can happen

Lack of illumination.

Symptoms: plants are thin and weak, leaves are pale green or yellowish (chlorotic) stems are thin. Fewer leaves and very small leaves on plants.
Near the light source plants grow fast, plants like cambomba have nice green tops but no leaves below the top leaves.
Why?: To few or weak bulbs, bulbs without reflectors or too old bulbs.
Light duration is too short (less then 12 hours) or to many plants on the surface.
Remedy: light corrections in general, new bulbs, make the surface clear, or bulbs in other light frequencies.

Wrong water temperature.

With high temperatures the symptoms are the same as above.
With low temperatures plants will stop growing and die after a short while.
Why?: A to high or to low water temperature, to much difference between warmth and illumination or to much difference between warmth and nutrients.
When the temperature is high plants need more light and nutrients, when they have not enough light and /or nutrients they will show signs of a growing disorder.
Needless to say, plants "breathe" more at higher temps and use more oxygen (during "day" time) and provide more CO2 ( at "night" time).
With really high temps the oxygen production (photosynthesis) is lower than what they use.
In this case we will create a not enough oxygen situation and problems will occur.
Remedy: Check if temperature, light, and fertilization (possible) are correct or within the parameters plants or fish can stand. Otherwise replace the plant with another plant which can stand higher temps.

Wrong light color

Symptoms and solutions.

Long plants with a lot of space between leaves, due to much light in the red frequencies.
Small plants and wide growth, from light in the blue frequencies.
Insufficient growth and photosynthesis with light in the green or yellow frequencies.
Remedy: Use proper bulbs and combine the colors!!
Best, but expensive are the fluorescent or bulbs in the day light spectrum.

Substrate problems

Symptoms: Rising gas bubbles when stirring the substrate. Plants won't grow.
Crypto's will grow their roots above the substrate. Malaysian trumpet snails wont dig in, they stay above the substrate (see, not all snails are bad)
Why?: A cloughed or old bottom substrate.
Remedy: Loosen the substrate and meanwhile suck the mulm away.
That way the gasses will leave the substrate while stirring the bottom.
About 2 days later you definitely have to clean your filter.
A week later you can fertilize again.
If plants aren't growing or aren't recovering you have to get rid of the substrate and install a new one!!
Perfection: It is better to re install new bottom substrate every 3 years.

Nutritional problems.

Errors with the Fertilization regimen can result in considerable damage to plants and disruptions to the aquarium environment !! We really want to avoid that !!

Lack of oxygen ( O2 )

Symptoms: Fish are stressed or are hanging near the water surface gasping for oxygen.
Without 02 for too long, plants and fish will decline.
Why ?: Insufficient light or fertilization therefore plants can't assimilate and produce oxygen.
The nitrogen cycle decreases because bacteria (aerobic) work slowly or not at all !!
That will result in too much C02 and water that is strongly polluted with waste products.
Remedy: Check the lights, fertilization, filter system, fish population (overstocked tank) and maintenance (errors).

Insufficient carbon dioxide ( CO2)

Symptoms: Plants tend to stay small and are not growing fast.
Rough sediment on plant leaves and ornaments due to biogenic decarbonation.
Why?:
The symptoms even can occur while dosing fertilizer properly and having a good maintenance regimen. 
Strong surface agitation due to strong currents (water outlet) and air stones.
Wet/ dry filters.
Remedy: Install CO2 equipment.
Decrease water agitation by not using air stones or drip tubes.
Note !! When using a wet/dry filter adding CO2 is useless !

To much carbon dioxide (CO2)

Symptoms:
Fish gasp at the water surface (danger due to suffication )
Why ??:
Insufficient oxygen levels due to adding too much CO2 ( above 30 mg/l), filthy and very dirty filter media, insufficient illumination, overstocked tank.
Remedy:
Check maintenance regimen.
Adjust CO2 equipment to the proper levels ( needle valve and bubble counter)
Switch CO2 equipment off during night time.
Adjust fundamental maintenance to the environment and water parameters of your tank !!

Phosphate overload

Symptoms:
Leaves die due to forming iron phosphate which we can recognize as brown or black discoloration on the leaves. Combine this with possible high amounts of nitrate and it will result in explosive algae growth !!
Why ??:
Insufficient water changing.
Remedy:
Adjust water changing regimen.

Nitrate overload

Symptoms:
Strong algae bloom, especially with high amounts of phosphate
Why ??:
To much feeding, filthy filter equipment and neglected water change regimen.
Remedy:
Adjust feeding regimen and change water regularly.

No trace elements

Symptoms:
Yellowish glass like leaves which will rot !!
Why?:
Insufficient fertilization regimen, phosphate overload and incorrectly dosed tanks ( fertilized) alkaline water or to hard water can be the problem.
Remedy:
Use PMDD or "manure" containing iron. See to it that the plants will get their trace elements regularly.
Lower the carbonate hardness when possible.

No manganese or potassium

Symptoms:
Leaves are yellowish but the leaves veins are still green.
Why ??:
Occurs in tanks who are only fertilized with iron.
Remedy:
Use good quality fertilization drops which contains all the needed trace elements.

Leaf damage due to chemicals

Symptoms:
Fish medicine, snail poison or anti algae chemicals can result in leaf damage or bacterial (filtration) problems.
Every plant species reacts differently !
Sometimes immediately, sometimes after a few weeks. But the symptoms are the same, like suddenly the leaves become yellow and brown and die !!
Remedy:
Increase water changing regimen ( fi. 30 % every day) and / or filter over activated carbon for a week or so. A.C. will get rid of almost all the chemicals but remove it when your water has the right freshness again.
Important!!
Always act like the medicine/chemical manual describes. When you don't trust it under dose never overdose or better don't use it !!!!!
Remember there are more roads that lead to Rome !!!!!!
Finally !
If you intend grow the plants emers: Remember that insects and bugs can become a problem as well !!

Rob Charite & Walter Soestbergen