[Andrey Mikhalchuk] is trying to gather a base set of lab instruments. Specifically, he’s looking for hardware that will let him quickly filter solids out of a liquid. He first started by adding a cotton disk to a plastic funnel. It does the job, but when left to gravity it’s quite slow. He needed a way to speed up the flow even when the filter is heavily clogged with particulates.

There’s already a solution to this problem. It’s a glass container called a Büchner Flask. These feature a glass tube coming out from the neck. By hooking a vacuum pump up to this tube, reduced pressure inside the flask will pull the liquid through the filter in no time. Rather than purchase the specialty item, [Andrey] altered a rubber stopper to accept both the funnel, and a glass tube. This is a cheaper version because it uses a common conical flask but it works just as well. To create the vacuum, an altered bike pump was used. Check out videos of both hacks after the break.

If you’ve ever had a water leak in your home, you know the sinking feeling that comes over you as you walk through the door to the sound of running water. [Greg] knows this feeling quite well, having returned home to a sopping wet floor and an overflowing reef aquarium on more than one occasion.

Both of the overflows he experienced were due to a clogged drain in his display, but there was little he could do as far as walling off the drain from potential blockages. With all of the delicate creatures living in the tank, the only possible solution that came to mind was monitoring the aquarium’s water level.

Unfortunately he had no idea how to get this done aside from using probes (which would rust in the salt water) or expensive off the shelf systems. [erich_7719] from the All About Circuits forums helped [Greg] out and designed a circuit for him which would monitor the water level using an IR sensor. The circuit simply shuts off the pump if the water level gets precariously high. As you can see in the video below it works quite well, and as a safety measure, requires a manual restart of the pump once the high water sensor has been tripped.

If you have a need for the same sort of setup, swing by his site for a detailed schematic as well as a bill of materials.

Keeping live plants in an aquarium happy can be quite a chore. One of the frequent rituals is adding fertilizer, which is called dosing. [Majstor76] came up with a creative way to automatically dose using an air freshener. He got rid of the canister that holds the scent and re-purposed a hand soap pump to move the nutrient-rich liquid. After the break you can see that there’s no shortage of power to actuate the pump and the powered air freshener base has a delay circuit, allowing for a few different time-release options. As long as the volumetric output is fairly consistent we figure you can dilute your fertilizer to fine-tune the dose.

[Thanks Chris]

If you want happy fish you’re going to need to do regular aquarium maintenance. Part of this is exchanging a portion of the tank’s water on a regular basis. [Bill Porter] came up with a water exchanger that means less manual labor, but makes the process just a bit more complicated.

So, what he would do before is fill a few buckets from the aquarium and dump them down the toilet. Then mix up a few buckets of salt water and add them back to the aquarium. This meant carrying several trips worth of heavy, dripping buckets through the house. What he has now is a gravity fed system into the orange bucket with a bilge pump to evacuate the old water from that bucket into the kitchen sink. The bilge can then be used to circulate water through the aquarium and the bucket, while filling with a hose from the kitchen sink and mixing in salt and chemicals. Less trips, no drips, but you’ve got to know what you’re doing with all of those valves.

We love seeing aquarium hacks like [Bill's], or cooling the tank lights while heating the water, or just a fancy lighting setup in general. So if you’ve got some of your own, don’t forget to send in a tip about them.

[Ken] found that using traditional tweezers is a good way to lose tiny surface mount parts and so set out to make his own vacuum tweezers (PDF). He already had a small aquarium pump that he used as a bubbler for etching circuit boards. After opening up the case he found it was possible to connect tubing to the input of the pump to use as the source for the vacuum. The business end of the device is a syringe which he already had for applying oil in tight spaces. A file took off the sharp tip, and a small hole lined with a bit of soft tubing serves as a valve. Put the needle tip in place and plug the hole with your finger to pick it up. Works like a charm and will go well with our next feature, building your own reflow skillet.

We like [Ken's] work. We just looked in on his copper clad enclosures yesterday.

With everyone’s favorite free-candy holiday approaching, [Slouriesr] set to work building a vomiting ghoul for his Halloween display. He’s calling it a puking pirate and it centers around a pump and some simple plumbing fixtures.

First, the vomit receptacle was made by adding a sink drain with a pop-up stopper to the bottom of a kitty litter bucket. The drain slows the evacuation of liquid into a five gallon bucket below. In that bucket you’ll find a float switch pump used to keep water off of a pool cover. As the bucket fills up the pump turns on and empties the water through a hose ending at the ghoul’s mouth. The result is a 20-second puke cycle sure to delight the trick-or-treaters. Sure, there’s a lot of work to be done to get this guy looking the part, but what a great idea!

Help keep us in the holiday spirit by sending the details on your latest prop build.

As the video above shows, [Zach Hoeken] is continuing to improve on his peristaltic pump design. The moving parts in peristaltic pumps never contact the fluid being moved. Instead, they interact with the outside of the tubing that’s carrying the liquid. In [Zach]‘s design, multiple skate bearings roll across the outside of the silicon tubing, squeezing the liquid through. You can get a better idea of how this works by watching the first video. The newer version appears to be pumping much better. We’re not sure if that’s because of faster motors or from switching to two bearings instead of three. This definitely looks like a good choice if you’re planning on building your own cocktail robot. You can find the plans on Thingiverse.