Analysis of fish Tanks in ESS prac room

During the ESS practical the class had been split into 4 different groups and were asked to record water chemistry results of the 3 different fish tanks which had been present in the room. Each group obtained  the chemical characteristics of the tanks' water through the use of  paper test strips. 


The test strip is dipped into the tank water, removed after a second and then held for a period of 60 seconds to observe a change of colour. The test strip with the water sample is then compared to the colour chart present on the tube. 


Chemistry characteristics of water Recorded by Groups:

Group1

	pH	NO2	NO3	kH	gH
TANK A	7.2	0	250	6	10-16
TANK B	6.4	0	100	0	10-16
TANK C	6.0	0	250	3	6

According to the results obtained above :

Tank with Best quality Water= Tank C

Tank with Worst quality Water:= Tank A

Group2

	pH	NO2	NO3	kH	gH
TANK1	7.2	1	250	6	16
TANK2	6.4	1	250	6	16
TANK3	7.2	1	50	3	3

According to the results obtained above :.

Tank with Best quality Water = Tank C

Tank with Worst quality Water = Tank A

Group4

	pH	NO2	NO3	kH	gH
TANK1	6.8	0	250	6	716
TANK2	6.4	1	100	0	10
TANK3	7.2	1	50	3	3

According to the results obtained above : 

Tank with the Best quality Water = Tank B

Tank with the Worst quality Water = Tank A

Physical Characteristics:

Tank A

• Lots of algae
• Algae on glass of tank.
• Algae on plastic cover of tank.
• Many fish
• Very few snails found under leaves of plants.
• Pebbles at the bottom of tank, not soil.
• 2 Under-gravel Filters
• Some leaves plastic.
• Water temperature: 28'C
• Normal fluorescent light
• 1 or 2 leaves busy dying 

Interpretation: 

The tank had quite a number of fish and could possibly be overstocked. This could influence algae growth.  Greater amounts of ammonia are present in the tank due to greater amounts of faecal matter as a result of the large number of fish in the tank.  Also with the greater amount of fish the more food is added to the tank which could result in more food falling to the bottom of the tank and decomposing, influencing the water's chemistry. The tank also contains plastic plants. Real plants take up nitrates in a water system, but as a result of plastic plants in the tank less nitrates is taken up which could explain the great amounts of algae in the tank. Another observation made is that the tank contains a trickle filter. This was discovered when sighting the use pebbles at the bottom of the tank. One of the disadvantages of this filter is that leaves from plants in the tank can easily get trapped in the tray. The pieces of leaves which end up trapped in the tray could decompose and influence the water's chemistry. Plants within the tank were beginning to turn brown. It was noticed that 1 light was present in the tank resulting in not enough light been provided for the plants in the tank. Due to the this reason the plants in the tank are beginning to die and less nitrates are taken up. 

Tank B

• Water temperature: 30'C
• Tiny fish
• Algae present between plants
• Water quality appears bad
• Many snails in the tank
• Thick plant cover at the surface of water
• Single plant at the bottom of tank
• No plastic plants
• Soil as well as pebbles at the bottom of tank. 

Interpretation:

Thick plant cover was noticed at the surface of water. As a result of this cover less light is able to travel through the plant cover. In this tank only a single plant was sighted at the bottom of the tank. Plant growth could be poor due to the result of the lack of light at the bottom of the tank due to the thick plant cover at the surface. Algae was found growing between the thick plants at the surface.. This indicates that there is light at the surface of the tank being used. Despite no plastic plants being present in the tank algae was  abundant due to not many plants in the tank.

Tank C

• MANY plants
• Plants cluttered in tank
• Water temperature: 28.82'C
• Streaks of algae between plants as well as algae at bottom of tank
• Many snails in tank
• Snails appeared in clusters on floor of tank
• Smaller snails compared to Tank A and B
• No plastic plants
• Plant matter at the surface of the tank water
• Filtration pressure stronger, therefore better filtration. (can be seen through circulation of plant matter at water surface)
• Substrate at the bottom of tank
• Fluorescent as well as UV light in tank
• Chemical filter
• 5 different types of fish (zebra patterned fish found)

Interpretation:

Tank C was found to have less algae in the tank when compared to tank A and tank B. It was observed that this tank had a better and stronger filtration system than the other 2 tanks. This observation was made through the sighting of plant matter being circulated at the surface of the tank. As a result of a stronger filtration system algae growth is disturbed. Due to a stronger filtration system less algae, compared to tank A and B, was found present in the tank. The tank also had an abundance of plants in the tank. This could be due to sufficient light in the tank as the tank contained 2 lights, namely: UV and fluorescent lights.