thanks!
thanks!
seeing the aquarium in operation is the only way to truly appreciate the water motion going on inside it but I'll try to explain what's happening.
a picture of your penductor would be great. If you could, list all that you use for circulation and about where they are in your tank. Please???
I just move into my new old house. I am about to build a fish room for a large tank. 72X36 and 28H. I also would like to have optimal flow for the tank without use a huge close loop like I did in the past. Plus a numbers of PH in the tank.
I'll start with some pix taken when the aquarium was being set up
drains and water returns connected to the basement sump are at the left and almost totally hidden between the aquarium and the wall. The water return line comes up and over the aquarium at the top left and breaks into two lines that run parallel along the top inside edge of the aquarium on both sides. These water returns are partially submerged and attached to top braces with nylon tie wraps. I drilled one anti-siphon hole along each length of return. (That's not a new idea). By directing the water discharged from each anti-siphon hole towards my rockwork I created some very interesting water movement... so I drilled some more holes along each return. (Now
that's a new idea!) I'd never seen this done before but it worked out great. When water returning from the penductors hits the small jet streams coming out the anti-siphon holes I get some really interesting water flow patterns (especially when a vortex is created and some micro bubbles get injected into the aquarium!) but this is all somewhat minor compared to the overall gyre.
Both return lines discharge at the top far right where you can see two 90 degree elbows directed back towards the drains.
Basic good aquarium design involves moving water to the drains

Without penductors the total water volume (GPH) being pushed out those returns equaled the total GPH volume going down the drains. This arrangement worked well but was improved upon by the addition of penductors.
drains and water return split
the penductors:
This pic was taken shortly after capping the water return with a penductor. I was worried about fishes getting sucked into their vortex but my fears were unfounded. (It might be another story with anemones that live on a reef crest.) Simply put, penductors are mixing eductors designed for aquarium use. They use a venturi effect to draw water surrounding the penductor into them. Make sure to get the appropriate sized penductor for your particular application. (There's a page earlier in this thread that briefly discusses sizing.)
the MJ's and Tunze Stream:
refer back to the very first photo in this post and you can see my unmodified MJ1200's at the top left corner of the aquarium. MJ's are great right out of the box and mine remain unmodified to this day. The MJ's are on a simple on/off pattern controlled by my ACjr. A little over a year ago I added a Tunze Stream up there as well. The Tunze is on a simple high/low pulse pattern provided by Tunze's most basic controller.
At one point I had a DIY Magdrive 9 powerhead but when it kicked on it's noise was not appreciated by certain other people in my household

If it was up to me I'd still have it in my aquarium.
Earlier in this thread I posted some pix that can be used to somewhat illustrate water moverment in my aquarium. This shows a water surge being pushed by the MJ's against the prevailing gyre created by my penductors.