Aquaponics - Float Valve Mod

I installed a float valve on my aquaponics system because I grow a huge sphere of slime in there as free food for my Golden Comets.

I'm currently making a half hearted attempt at breeding them.

My Float valve looks exactly like this pictured to the left.

I bought it on eBay for two dollars I think.

It works pretty well but it doesn't put out a lot of water. I'm guessing it was designed to keep a dog bowl full or something, and for this it would be perfect. But I need a little extra flow.

Here it is in it's full "on" position.

And here in it's "off" position.

It does "off" pretty well, although I'm not overly fussed about it's "off" state. I dont really care if it leaks a little.

As you can see from the black pipe leading into it, there are some holes to make a spray to add a little aeration, but also to make sure there is never a situation where there is zero flow.

I only have a dozen or so adult goldfish in my system, and it is capable of holding a lot more.

 It could cope without any flow for a day or two, but the fish seem to enjoy their water moving around a bit.

The problem is that the slimeball I'm cultivating in the tank can sometimes find it's way into the outlet. The result is an overflow, and the sump tank running dry. The pump hates it when that happens, and I was lucky enough to catch it just before it ran dry a couple of days ago.

The point of the float valve was to slow the amount of water entering the fishtank if the water level gets too high. But because the flow through the device isn't very high, it isnt quite doing the task I assigned it.

I decided to make it flow a little faster.

To this end, I taped out the pin that holds it all together with a chopstick.

As expected, everything fell apart nicely, and I found that the thing worked by the float levering a small slide with a silicone stopper on the end. This blocked the water outlet when the float was
... floating

The bottom bit has the float on the end and fits into the box section on the next bit up. The lowest bit of green slimy plastic is the silicone stopper that presses against the next higher up bit of green slimy plastic.

I should write operating manuals.

The inlet hole did indeed turn out to be pretty small. Perhaps this is so the silicone stopper has a nice large surface area to stop leaks.

But I dont care about leaks because even when the slime blocks my system, it always lets some water through.

It never blocks it perfectly.

So I drilled it out to a size that should let more water through, but still allow the float to shut down the flow.

I had to do it by hand because the chuck on my drill has decided that it likes having the 13mm drill in it and refuses to surrender it no matter how I try to persuade the thing otherwise.

Thats what you get for running water all over the chuck when drilling stainless hinges and trying not to overheat the drill bit.

Somewhat surprisingly, the thing all fell back together as easily as it fell apart.

A few taps of the pin and it was all good.

So now the flow looks like this when it's in the "off" position.

Not a bad result.

Most of that flow is because I didnt bother to clean up the hole I drilled.

"Drilled" is probably a bit of a fantasy really.

Lets just say I made a hole with a drill bit.

In the "on" position I get a lot more flow now.

All in all I think this can be called a complete success.

And perhaps more importantly, it  shows that maybe I can still do stuff.

It's been a while.

If I care enough, I'll clean up the hole and make it so the flow actually stops when the float is floating.

Trying to drill by hand is fine until you actually make it through the thing your drilling. Then it becomes very difficult to make a clean hole because the drill bit just tries to screw itself into the item.

This is the "before" shot.

And this is the "after" shot.

The result is you get three quarters of a hole as you brake through the plastic.

I'll file it back to something like round if it turns out to matter.


I did something.

120ThingsIn20Years Some of the photos were even in focus!


  1. You are hilarious and I really do laugh out loud at each post. Thank you!

  2. You seem to be reading the entire blog. That or you just happen to have a specialised interest in every single thing I do, and need those exact facts that I happen to know.

    Either way, it's nice to get the feedback :)


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