Hydor Crystal Mini Internal Filter - review

While cleaning the shrimp tank out, I noticed the internal filter was goosed so it was time to do something about it. With the aquarium lacking in space and not wanting to go down the external route, I really wanted a small reliable internal that would fit neatly into the corner of the tank without spoiling the look of the tank.

After a bit of research, I decided on one of the internal filters from Hydor. There were a few features that looked good and the main one being the anti-waste dropout system. If there is one thing I hate is the detritus waste spewing into the water as you take our your internal to clean it. Its brutal. The way this filter is designed, you unclip it from the corner bracket an lift the full filer out and nothing comes away. We will see how effective that is when it comes to cleaning it.

I also liked the size of the filter. just over 9cm wide and nearly 20cm tall, it would fin nicely in the corner of the tank.

Taking everything out the box and putting the filter together took about five minutes. From filling the media chamber with charcoal to clipping it onto the bracket was very quick and easy. The instruction manual is nice and simple to follow of you have never fitted an internal before but having installed plenty over the years, it was straight forward.


Out the box
Putting the filter into the tank was easy enough, I pushed the filter into the water and pressed gently against the corner of the tank and the suction pads held everything in place. I found directing the flow to where i wanted it was simple. With the option to twist the filter when its in the bracket allows for a left or right direction and with the little push on connector you can even direct the flow towards the substrate or surface. I wanted to direct the flow towards my Cryptocoryne  plants that had collected a bit of debris due to the existing internal filter not working correctly. As soon as i switched on, it kicked up all the debris and straight away I was seeing the particles of shrimp shells (previous molts) being sucked in through the intake on the brackets.

Simple but effective media 
What I found interesting is that the filter intake is designed to work through the actual cornet bracket and the rear of the actual filter. this works well on my shrimp tank because there are no large intakes for the smaller shrimps to worry about.

The option of a venturi air intake is here too but in not a fan of them personally. I did attach the tubing to have a look and it is very effective adding lots of bubbles but its not my thing.

The filter has been running now for 24 hours and my water is crystal clear, moving about very well in all areas of the tank and the surface has cleared up completely. There is a setting on the actual outlet which gives you the option of high and low. I Went with low because its being used in a shrimp tank. i did test the high and it was a notable difference but too much for me.

I wanted a small, reliable filter and this certainly ticks both boxes.

The crystal filter range comes a few sizes.


The crystal filter fits perfectly in the corner of my shrimp tank
  • 20-50 litre tank size
  • 40-90 litre tank size 
  • 80-150 litre tank size
  • 120-200 litre tank size
  • 200+ litre tank size

This filter has been around for a while now and can be picked up at a very reasonable price too. My model costs around £20.00. 

As far as negative aspects of this filter goes, Im not sure at this point if there are any. It feels sturdy, looks good, works well, easy to install. When the time comes to clean the filter, I will find out how good the anti drip feature really is and ill let you know.

To summarise 

If your after a solid little internal, with out spending a fortune, these filters are worth picking up. As far as negative aspects of this filter goes, Im not sure at this point if there are any. It feels sturdy, looks good, works well, easy to install. When the time comes to clean the filter, I will find out how good the anti drip feature really is and ill let you know.

Our upcoming Scottish event on the 10th December will have a range of Hydor products on display with the chance to ask the team any questions you may have. Hope you can make it.