Last June 6, 2011 the Laguna Lake Development Authority did water quality tests in Laguna Lake for levels of dissolved oxygen or DO.  That is very important because fishes need a lot of oxygen to survive. When there is not enough oxygen there is a fishkill like what happened in Taal Lake a few months ago.  We have to remember that letting our trash to wash into the lakes because we don't throw them properly can cause the DO to drop and making it dangerous for the fishes in the lake. 

It is important to monitor the lake waters so the public can be warned if there is a problem.   I also do water quality monitoring in our lakes in San Pablo City just to make sure there are no major changes. I don't know who does scientific testing here but I do it with my own simple test kits.