Why is sand filter blowing algae back in pool while vacuuming?

Answer 1

Im not an expert by any means but what I know is that with a sand filter system if your pump is not the corect HP for the filter it will push dibris and sand right back into the pool

answer::

That may be true in remote cases where the system was not installed correctly or had well balanced/matched equipment. The correct answer would most likely be that you have a broken lateral(s) which allow sand to pass back to the pool. It is best to find the correct type lateral for your specific filter. Some manufacturers have made modifications to same model filters as production and technology progresses. Replacing the lateral required turning the equipment off and making sure it will not come back on while it is being worked on. Removing the filter top or valve assy. Removing all sand, finding the damaged lateral(s), replacing lateral, replacing the sand with new sand in the correct manner, replacing the valve or filter top and starting the equipment and backwashing the filter to reduce the dust blow back

K

Answer 2

A number of things could be causing the problem. It could mean that a lateral is cracked or broken, or a valve may need servicing. Or, air may be passing through the filter, causing a channeling effect that permits dirt to get by the filter. In the latter case, there may be nothing wrong with the filter. If you are getting a lot of sand in the pool there may be a lateral broken in the bottom of the filter. If this is the case, the lateral(s) will have to be replaced.

Answer 3

Aside from the possibility that some one has thrown it in there the only possibility I can think of is that the laterals in the sand filter are worn. when that happens sand will be blown out of the pool returns. Cure; empty sand filter replace laterals refill sand filter.

Answer 4

Most likely you have a sand filter unless you live near the beach. The sand filter has baffles inside the filter and buried down in the existing sand. One or more of the baffles or the stack pipe is cracked. causing sand to return to the pool with the filtered water. Drain the sand from the sand filter and replace the baffles and/or stack pipe. Replace with new sand. Be sure to use approved sand for sand filters.

Answer 5

The "spider gasket" inside the valve has been destroyed by the chlorine and the water is blowing through the valve instead of going through the sand. Take the cover off of the valve by removing the screws on top and examine the gasket beneath. If this is not the problem, then I would replace the sand in the sand filter. Pool Masters

Answer 6

It sounds as though one or more of the laterals in your sand filter are in need of replacement. when these become worn they do not hold back the sand in the filter and it ends up in the pool.

Answer 7

if sand is returning through your jets, the sand filter needs to be replaced. laterals located at the bottom of the filter are broken allowing sand to pass through