If I plumb my filter installation as shown below will it work for draining the tank, refilling it, vacuuming the substrate, and topping off the water level? The water would come from the cold water plumbing, going through a regulator, throttle valve and filter. The drain would go to an open pipe where the water would be collected in 5 gallon buckets for watering container plants.

These valves would be under the tank, in the enclosed stand.

EDIT: Illustrations revised, old version that was here omitted.

I'd want to drain the water through the filter's output line and on out to the in line to outside/drain etc, basically the reverse direction that normally filters run.

So you need a drain tee valve btw the intake from the tank and inlet for the filter. This drain Tee right before the filter will direct the water out to the drain.
When you turn it the "off", it by passes the draina nd heads on to the filter or back up to the tank.

By blocking the tank return and running the siphon in reverse, you back wash your filter.

So the outflow from the filter is now the siphon out of the tank.
But instead of leaving via the intake in the tank, it drains out to the yard etc.

You also need a by pass loop for the CO2, it'll get mucky.

I think all you need to do is add another valve up stream from the drain on the intake side of the filter.

That will block off any return or siphoning from that end of the plumbing.
That and if you do not mind running most of the water change backwards through the CO2 system(not an option for me due to the venturi and needle wheel).

Also note: if you switch the fill and dump/drain lines, you can flush the filter with the tap water in reverse if you also add a valve just upstream of the Tee on the intake side of the filter.

That would be the best solution, then it does not matter which direction you go with the draining, you can easily backflush the filter as much as you want without any water change(unless you prefer).

Regards,
Tom Barr

Thanks Tom. My problem with setting it up as you suggest is that my filter output goes to a discharge fitting that is near the water level in the tank to give me more surface movement if I want it. So, I can't siphon out of the tank from that fitting. I could lower it to near the bottom of the tank, and add a tee outlet fitting with loklines on each outlet, as you are doing in the big tank, but I wasn't planning on trying that yet.

I only want to change about 25% of the tank water, twice a week or so, otherwise I get too much drain water to store - it is a 45 gallon tank. I have no good place to dump the drain water directly, since I am in a condo with this set up on the second floor.

My gut feeling is that I prefer to manually clean the filter, just so I can see what's happening in there. I'm still thinking this over though.

Hi Vaughn,

Can you make the fitting for the drain outlet one that you can cap off when the T valve is closed and then easily place (quick connect fittings) a FLEX hose on when needed?

I use a 500gph pump and 10-12 feet of flex hose to drain my 180 for WC.

I drop the pump in the tank and send the flex hose right down the kitchen sink with no issues at all..........if it was long enough the bathtub would also be available or just out the door (am on 1st floor with THIS tank lol). If the pump will reach longer you have more options.....

The flex hose can be coiled easily and stored till next time.

I realize this is more manual than you would like, but would allow you to change more water if required and eliminate the reliance on the tubs....At least until you figure the permanent solution out.......

Also allows you the thrill of cleaning the filter manually............

I like your idea and wish you the best of luck!

Yes, I could use a "drop-in" pump to remove the water, but I already have a pump, the filter, with plumbing in the tank, so it makes sense to find a way to let that pump remove the water. Once you can wrap your mind around the idea of using multiple ball valves under the aquarium, lots of options open up.

I looked at the link Tom provided in another thread about a reef tank, which had what looked like 100 such valves under it. I laughed at the joke. Then started thinking some more. Those valves are not expensive, so with enough valves you can make the filter do just about any job you wish. And, Tom's idea of back flushing the filter is getting more interesting the more I think about it.

The key to using such a system is having all of the valves lined up, grouped by function, with a chart giving valve position for each activity you want to do. I continue to think about this and do sketches!

Incidentally, as a retired engineer, who worked on hydraulic systems for several years, this is very welcome recreation for me!

Vaughn,

Sorry I was unclear. I did not want you to switch to a drop in pump.

My idea was just the flex hose for the outlet which can easily disconnect for the issue below.



This can then drain to the sink or tub, outside as appropriate until you figure out a permanent way.

After more thought and sketching, this is how my schematic has evolved:



Seven valves lined up on a board, in the back of the cabinet, with an illustration attached showing how the valves are to be configured for the three activities: draining the tank backwards through the filter to flush it, normal operation, and refilling the tank. During the drain operation the substrate could be vacuumed, but that does dirty up the filter excessively, so I will probably drop that part. Any suggestions?

EDIT: Revised to include the overflow fitting in my tank, now used for a continuous water change system. This will now serve just to set the water level during refills.

Now that I have replaced my light fixture with one that lets me get easy acces to the plumbing behind the tank, I went back to this project. My final design for the plumbing is:



Today, I finished the basic assembly of the manifold, which ended up being too wide to fit the inside side of my cabinet, but it will fit against the back wall in the cabinet. I will use Eheim 16/22 hose to hook up the filter to the manifold and the rest will be routine. So far this is costing $40, with a few more dollars to go for hose barbs. Here it is:

I finally got this monster installed. It works! Well, most of it works, and eventually I may get all of it to work. First: here is what it looks like installed:


I spent 6 hours yesterday struggling with this, fixing hose barb leaks, then making numerous tries to re-prime the XP3 filter. I finally gave up on using the manifold to vent the top of the external reactor, and just opened the tube from the vent valve. It finally primed, but only after draining 5 gallons of water from the tank in futile tries.

This gave me the chance to try the fill valve function. That worked very well, but slowly, since the incoming water goes through a 1/4" drip irrigation tube that is about 20 feet long. And, that let me try the overflow drain function, which worked perfectly. Still left to try is the back flush.

I really like this, but the amount of work involved is so great it might not be for everyone.