I have to confess...I really HATE doing water changes.

when u got 15 tanks running u create solutions.... _here's what I did: _bought 35 FEET of hose (enuff to let it drain outside from any tank) & connected to siphon. _
1. goto shower/bath tub w/siphon & hose. _
2. place siphon end onto shower head & turn on shower. _
3. let water flow all the way thru & out the hose
4. as soon as most/all of the air bubbles are out, use thumb to plug up exit end.
5. when water reaches top of siphon, turn off shower.
6. cap off siphon w/other hand & bring to tank
7. place siphon into tank gravel & leave it (make sure it stays in place).
8. take exit end outside & toss into lawn.
9. come back & siphon away...
10. when ready for next tank, simply cap off siphon w/hand & move it to next tank.

a 50 foot python is ONLY used to re-fill, not drain. _I found out draining w/a python is a waste of water, literally (water needs to be running-esp if the sink is higher tank the tanks).
 
I use old fish water for my plants and trees inside and out. Seeing how healthy my plants are getting the nitrogen rich water and fish are getting fresh clean water makes it worth the trouble.
 
I always do a bucket or two the old fashioned way for the plants
out side. Then the rest with the python. My tank is in the kitchen next to a wall of cabinets and I can hook the python hose on the handle of the cabinets all the way to the sink! That way I can turn of the sink water and not waste it while draining the tank.
 
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