Another great addition to your garden is the water from an aquarium.
Dip out the well diluted fertilizer water and add more clean water for your plants. I use it on my houseplants too.
Then add clear water to the aquarium slowly to not disturb the fish. Make sure the temperature of the new water is comparable to the old. Repeat as the water gets cloudy.
The plants and the fish will benefit and you won't be throwing away a valuable resource.
