Posted by Bill on September 11, 2006 at 13:23:27:
In Reply to: Pea soup pond & fountain posted byDonn Pardue on September 10, 2006 at 15:10:04:
This is a problem we probably see two or three times a year. If you google it you can probably read for days, but here are the highlights. Algae is a plant, albeit it microscopic. To thrive it needs, sunlight, nutrients and to a lesser degree temperature. Obvious problems but if the sun exposure can be reduced this will help. Nutrients is the biggest factor. Anything decomposing on the bottom, like leaves, fish poop and uneaten food will 'feed' the algae= feed less and clean the bottom thoroughly (not the sides). If there is a thick layer care must be taken because toxic gases may be developing which if released by the fish may be fatal. Fish also secrete Ammonia as a waste product. In a healthy pond this gives broken down to nitrates which are a great plant fertilizer. So again if you feed them less and there are fewer of them (too many fish?) less growing material will be available. Macro plants (pond plants) will outcompete the micro plants (algae)if you have enough - so rooty pond plants in the pond, or submerged plants, like anacharis will help against algae. Another possibiity is a UV light. These cost a little more and will require a lower flow rate than the water features, but if properly sized will just kill the algae. Others have had better succees than, but Barley bales and extract, and cornmeal bags work by culturing a different bacteria to compete for the nutrients. Barley I have no experience with, but the cornmeal works relatively well. However it must be changed out every 10 days or so, or the decomposing cornmeal also becomes an algae nutrient. Products like Algae Fix are generally not recommended, They are hard on your fish and the results are temporary. As well the algae that is killed must be collected or it also becomes algae food for the next wave of growth. 10-15% weekly water changes will help a little bit. The pond probably will clear up quite a bit as the temps and daylight hours decrease, but this victory will only be shortlived till Feb or April if the root causes (pardon the pun) are not addressed.
Simple huh? Unfortunnately I know of several pond owners who have given up on there pond this because of suspended algae. In the long run practicing the basic principles I have listed over time, will produce a 'balanced pond' which will hopefully right itself year after year. Although April algae blooms are very common untill the plants start getting established again. First year ponds or ponds that have been drained and started over almost always have problem and the more algaecide and big water changes are used the longer it will take to clear up. And finally sometimes some years are just worse than others:( HTH
Bill