Another WC question, but...

[DN328]

...for those with fairly "large" fish and a sump - how are you able to do 80%+ in a single water change (assuming you don't have a constant drip or automation)? Are folks on canisters, etc. so able have a larger percent during WC? Not factoring in the sump volume?

There's only so much water that I can remove in a single drain without also replacing some water in the sump if I wanted to do more than say 50% in one WC. This is based on my tank/sump volume combo.

Some posts I've read got me thinking if there's something I can do differently to replace more water during a water change. I'm already going through the motions so mind don't mind changing more...

 

[Beetlebug515]

It really does depend on your tank/sump volume. I would just drain as much as I wanted from both, refill the tank and let the tank fill the sump.

 

[Woefulrelic]

I use a garden hose to siphon it out. Can't see why it wouldn't work here.

 

[duanes]

I agree it depends on the sump.
I use 75 gl tanks as sumps, with a water level maybe 3" from the rim.
When I do water changes, I take the sump water level down to the pump intake, maybe 2; from the floor of the sump, so a little over 50 gals at a crack.
On some tanks, I use 50 gallon barrels as sumps, again water level is within a few inches of the rim, and during WC levels are taken down to pimp intake level.


above is one of my planted sumps,
below that same sump during a water change

below one of my barrel sumps during a water change

 

[Woefulrelic]

I forgot not all set ups are gravity based like mine.

 

[duanes]

Although my systems were all flow to sump by gravity, when doing water changes, I close the tank valve and pump old water out directly to the garden or lawn.
Kind of anal about trying to get more than one use out of the water.
In winter I try to use old water in toilet tanks, to get that extra use.

 

[DN328]

I could drain my entire tank if I wanted relatively fast as I connect a hose directly to the closed loop plumbing. As mentioned, gotta leave around 8" for the aro.

The python doesnt work well at the sump level, and i guess I should do the old fashion syphon to bucket. Then just fill tank as usual until both are sufficient levels.

Ive also used a shop vac on the sump to remove water and remove any detritus. I just didnt want to fill with direct tap.

 

[Def Leppard Hysteria]

I just turn my pumps back on once the water level falls far enough below the overflows, so the water from the sump goes up into the tank without falling back down into the sump again. I let the pumps run until the water level in the sump drops to just right above my biological media.

 

[DN328]

I just turn my pumps back on once the water level falls far enough below the overflows, so the water from the sump goes up into the tank without falling back down into the sump again. I let the pumps run until the water level in the sump drops to just right above my biological media.

My bio media is also submerged to almost the height of the sump, so either I leave existing water as is, or, I pump back up to the main tank (without going back down the overflow), then remove.

Either way if i want to remove more overall water volume to increase WC %, the sump will need to be filled with tap water. I guess no way around that.

Clear as mud? LOL

 

[Def Leppard Hysteria]

My bio media is also submerged to almost the height of the sump, so either I leave existing water as is, or, I pump back up to the main tank (without going back down the overflow), then remove.

Either way if i want to remove more overall water volume to increase WC %, the sump will need to be filled with tap water. I guess no way around that.

Clear as mud? LOL

Yep. Makes perfect sense to me. I just let the treated water make its way back into the sump once the water reaches the overflows. Once the water level in the sump reaches the desired max point, then I flip on the pumps.