reusing fish water

[Calico3]

Hello folks. I would really like to water my grass and outside garden using some of the water from my many fish tanks.  Presently I use a python water changer and the water goes down the sink. A waste and it would be nice to cut down my water bill this summer. Unfortunately I missed the pond discussion and now am considering a utility pump and the purchase of a water barrel to collect my excess tank water after water changes during warmer weather.

Does any one in the forum do this ?  I have a rain check on a 1/2 HP pump at what I think is a excellent price.   Is this too large for my use ?    What is involved.   Many thanks

[tanksalot360]

Highly recommend!
Rain barrels are a good price at Cohen&Cohen just FYI (but had to rinse because there had been food in the barrel). And if you elevate the barrel, you can use gravity to water your plants - either siphon or install a bottom drain/tap.
When I worked on ponds, I would water change onto the surrounding gardens. Aquaponics works based on this concept too.
Are you looking to pump the water out a window or door? I found a sump pump (1/4 hp i think) at C Tire that had a garden hose fitting which was very convenient for large volumes, but im sure you can use your python hose with the right connectors (I might take it a bit further and get garden quick connect fittings if you're going to be using the pump often and want to make it easier on yourself).  As for the pump, are you trying to pump water up and out, down and out? (If you're pumping up, consider potential back siphoning issues.)
The head-height rating on the pump will help you with this as the flow rate will slow down if it has to work against gravity.
Is the pump going directly in the tank with fish? Is the intake appropriate?
Just some considerations.