1. 9-26-13Starter: If you had to create a hypothesis to test your water at home, would you say it is hard or soft and why?

2. Water Quality Parameters  Temperature - Dissolved Oxygen (DO) - pH  Alkalinity - Hardness  Nitrates and Phosphates  Turbidity

3. Temperature  Most aquatic organisms are cold- blooded and have an ideal temperature range  Affects the development of invertebrates and metabolism of organisms  Affects dissolved oxygen (warm water holds less oxygen)

4. pH  pH scale ranges from 0-14 (0-6 acidic, 7 neutral, 8-14 basic)  Measures the degree of acidity or alkalinity of the water  Ideal pH for fish: 6.5-8.2  Ideal for algae: 7.5-8.4  Acidic water makes toxic chemicals more toxic than normal

6. Phosphorous/ Specifically Phosphates  Phosphate (PO4)-3 naturally occurs in rocks and minerals  Necessary component for animal and plant growth  Natural sources of phosphorous: phosphorous-containing rocks  Human source: fertilizer and pesticide runoff  Can stimulate algal growth and bloom

7. Nitrates  Formed by the process of nitrification – the addition of 02 to NH3 by bacteria  Naturally occuring in soil – ( NO3-)  Used by plants and algae  Mildly toxic, fatal at high doses  Large amounts (leaking sewer pipes, fertilizer runoff, etc.) can lead to algal blooms

8. Dissolved Oxygen (DO)  Oxygen that is dissolved in the water  DO increases with cooler water and mixing of water  Nutrient overload can lead to algal blooms which = decrease DO  Expressed in parts per million (ppm)  0 -4 ppm = bad  5 -10 ppm = good

9. Tyndall Effect  Scattering of light particles in a colloid (fine suspension of particles in a solution)  the phenomenon in which light is scattered by very small particles in its path; it makes a beam of light visible; the scattered light is mainly blue  Affects turbidity of water  Occurs after pollutants and or soil from runoff have been introduced into the water supply

11. Turbidity  Measures cloudiness of things, in this case water  Due to plankton, chemicals, silt, etc.  Common causes: plankton, soil erosion (due to mining, logging, farming, construction) and algal blooms due to fertilizer runoff

12. Turbidity Problems  Photosynthesis may be reduced or even stop  Algae and plants can die  Can clog gills of fish and shellfish can be fatal  Fish cannot see to find food but can hide better from predators

13. Soft Water  Soft water: only ion is Sodium (Na+) - may taste salty and not be safe to drink -natural source: granite

14. Hard Water  contains a substantial amount of dissolved minerals like calcium (Ca2+) and magnesium (Mg2+) -Negative effect on plumbing and makes some cleaning materials less effective -Natural source: limestone -Ex: San Antonio water