Art by Alexander Vasiljev, Copyright © 2017


Friday, November 22, 2013


To house the fish I ordered a 120 gal fiberglass pond (L 96 in x W 24 in x H 12 in).

Fiberglass Pond

In traditional ranchu keeping there are no conventional filters used, besides algae growth and an air-stone. Absence of filter requires 100% water changes every 4-7 days. Most importantly, it requires you being available to do the water change every 4-7 days. Pretty tough commitment for a traveling enthusiast like me.

So, I had to have a back up and designed a filter for mechanical and biological filtration to control ammonia and nitrites levels. A stand alone sump tank housing various mechanical and biological filter media would perform this role. After many consultations with the folks on a couple of forums, I have come up with the final design. I loaded the chambers with Eheim Substrate Pro Bio Medium and Seachem Laboratories Matrix Medium for biological filtration. For biological/mechanical filtration I used Matala Filter Media mats, two more finer filter pads and to "polish" the water - filter-floss.

Sump Tank, Side View

The water is pumped from the pond into the sump tank and then let flow back to the pond through the media by the gravity. I also placed two large air-stones in the pond hooked up to an air pump.

Entire System Set Up, Top View

The pond was set up in my apartment and had to look esthetically pleasing with most wires and hoses being hidden away. So, I designed and built the inclosure, trying to complement the fish in the most humble way. My goal was to achieve a good balance between functionality and esthetics. I even used plants around the pond commonly called "cast-iron plant" Aspidistra elatior from Japan. Ironically, its leaves were traditionally used for preparation of sushi battera style. Shh, I will never reveal this to my ranchu.

Almost Finished Pond Set Up

I wanted to have a water feature to complement the installation and came up with an idea of a bamboo aqueduct. I used a second "miniature" pump to pump small amount of water from the sump tank into the bamboo "pipe". The water runs through a couple of bamboo pipes, creating a beautiful trickling sound and gets aerated before porting back to the pond.