Fluval Flex Intake Pre-Filter / Baby-Safe

After I bought a Fluval Flex 35l/9g (okay... just because it looked nice) I quickly noticed some flaws and / or opportunities to tinker :-)

So I started to redesign and add some things. This is Part 5 of the project.

The whole project will cover cooling, heating, light control, water refill (and whatever idea I will have in addition) using an ESP micro controller and is without any destructive modifications to the tank hardware.

The original Filter intakes are covered by two plastic pieces which are often seen stuffed with filter sponges to prevent (baby-)shrips from getting into the filter compartment. This is an easy way to do it, but I am a Maker and also changing the sponge in the lower one is a mess.

So I designed a holder for the filter compartment side which can be easily mounted by using two small plastic clips.
This holder takes three different inserts, depending on what you need.

The first one (basket) is a full size basket, which can be equipped with filter wool or a filter sponge. This will act as a massive mechanical pre-filter and helps clearing water.
There are 3 clips (clip_long) included which can be snapped into the basket for holding the filter down while inserting the basket into the holder.

The second model (basket_singles) has two seperate compartments for those who want to save some filter material or use different materials for the upper and lower intake.
Here only the lower one has a clip (clip_short)

The third model is for adding making it just baby-safe without any filter. You can pull a nylon sock over the suspender (sorry, I had to call it that way ;-) ) and slide it into the holder directly. Take care on the orientation!

The whole thing is quite easy to fit into your tank. Just insert the holder from the filter compartment side, slide the lover "hooks" through the filter slots in the back wall and then slide in the upper ones and secure it with the two clips:

Now I can easily clean the intake filters, without having to worry about pulling our some plants or squeeze some shrimps :-)

• The models should be printed in the orientation of the stls (maybe rotate the case 90° around Z).

All models can be printed without support - but remove the integrated supports (red in the picture) from the holder, before inserting it into the tank: Print:
Always:
1x Holder
2x clip

Option one:
1x basket
3x clip_long

Option two:
1x basket_singles
1x clip_short

Option three:
1x suspender

Use PETG, PA or any other food safe material (preferably without colour) and water the model for at least 24h before inserting it into the tank. If you plan to switch to other bio filter media, insert it in the lower basket and the used one in the one above. leave this for at least 4 weeks before you remove the old one.

Category: Hobby