COD vs. TDS vs. Chloride

1. Swimming Pool
2. Pond ( General )
3. Pond ( Girls )

From the bar graph, we can see that the cod, TDS and chloride are being compared between the pond and the swimming pool

Two readings from the pond was taken and the results are slightly different. This is so as one sets of the reading is proven to be inaccurate.

The readings of the total dissolved solids of the pond stands at 84.5 and 74. (the main difference between the 2 sets of results)

Other than the TDS measured, the other sets of readings, both the cod and the chloride, is almost identical in both sets of the pond readings. other than the TDS measured , both the cod and the chloride, is almost identical in both sets of the pond readings.

As compared to the pond, the swimming pool has a much higher content of chloride. This is so as chlorine is used to disinfect the swimming pool.

The swimming pool also has much more total dissolved solids than the pond due to the fact that many people swam inside the pool. Copper sulphate, chloride, suntan lotion from human skin and algicide are plentiful, hence resulting in a high level of TDS(756.4).

The chemical oxygen demand test is used to measure the pollution strength of domestic and industrial waste water. Therefore, the cod level of the pond should be higher than that of the swimming pool due to the fact that the pond contains a higher level of biodegradable and non-biodegradable components. Another reason is that the swimming pool is usually cleaned and maintained. Although the pond is also cleaned and maintained every week, but the presence of fishes and birds produces wastes which contributes highly to the cod level of the pond.