Mash Transfer with Aquarium Pump Question

[Mr_Beer]

Looking for some answers to use of aquarium type pumps for transferring mash results.

My process is to ferment on-grain in 20 gallon HDPE containers that have 800 micron mesh bags in the vessel. The bag is lifted with a pulley system and allowed to drain. It can be squeezed effectively as it is draining. Almost as good as using a press to squeeze the fermented results.

What is left is liquid, some minor amounts of stuff in suspension and of course the yeast residual at the bottom of the HDPE barrel.

I want to transfer that liquid to intermediate containers for settling for several days and then transfer that result to the boiler for distillation.

I have tried two transfer pumps from MooreBeer – one for about $85 and the other for $190. The first failed almost immediately – the small amounts of sediments in the mash ‘blew out’ the pump diaphragm. The more expensive pump has a pre-filter that is so fine it clogs up within a gallon or so of starting the transfer. My advice is to avoid those pumps for this application.

So the next notion is to use an aquarium pump inserted in the barrel. It would pump out the material – low head of less than 4 foot. Sort of the equivalent of a trash pump used in construction and de-watering activities. There would be no attempt to pump the yeast residue but some will most likely get disturbed and transferred.

Anyone had experience with this approach?
Opinions?
Other ideas?