Simultaneous Water Change System

[doctor_random]

An engineering-type question regarding a water-change system I'm trying to build.

Currently, I successfully remove water from my DT using an Aquatec 8800 pump which is hard-plumbed to a drain under my kitchen sink. I can pump about 1-2 gal/minute with this setup.

I have a fresh mixed salt-water reservoir about 4 feet below the DT. I currently pump water out of the DT with the Aquatec 8800, and then follow by replacing the waste water with new salt water from the reservoir. I use a MagDrive pump to lift the new water into the DT. Moving the new water is very messy, and volumes are difficult to match.

What I'm looking for is a way to use the Aquatec 8800 pump-out flow to drive a pump (i.e. a water-driven pump) which will lift the new salt water into the tank simultaneous with the pump out. I don't want to use two electric pumps.

Yes, I understand that using this simultaneous system will make water changes less effective at diluting DT waste (turns the tank into a differential calculus problem...) but I will do them more often if I can build this set-up.

Any ideas? The Aquatec "permeate" pump won't generate enough flow, according to Aquatec support.

 

[cali_reef]

I don't think a waste water driven direct connect pump will have the energy to drive a fresh water pump at the same rate. There will be losses to friction and head pressure.

Look into Dialyseas if you want a system that is fairly complicated to continues water exchanges.

Sounds like you have a sumpless system?

 

[doctor_random]

Water Change system

I don't think a waste water driven direct connect pump will have the energy to drive a fresh water pump at the same rate. There will be losses to friction and head pressure.

Look into Dialyseas if you want a system that is fairly complicated to continues water exchanges.

Sounds like you have a sumpless system?

The head pressure of the waste pump is much greater than the 4 foot head on the fresh water pump, so the physics might work out, actually, but I've been mulling over this conservation of energy issue...

I do have a sump (and refugium) but they are on the same horizontal level as the DT (flanking the tank) engineered for overflow prevention in my apartment. Water level management is somewhat complicated, so adding a water change system is also complicated...

 

[Fudge]

heres an idea, us the same pump for both waste and return , u will need to plumb this under the tank so u will not havto prime the pump everytime and use a t conecter on both ends of the pump and use valves to switch the drain side off when using the return and vise versa.