Spraybars 101

[meegosh]

So here's the situation... I have a standard 4' 75g tank with a Fluval 406 running. The flow is plenty strong but leaves some dead spots. I want to make my own spraybar.

One of the most common things I see about spraybars is that if you go out of town and your water level drops, it can empty your tank. How is this possible? Do people drill the holes so they aim upwards? I thought these were supposed to make current across the surface, not shoot water upwards at the surface.

Maybe I'm missing something... I'm also thinking about designing it so that if the water level drops it can easily be pushed down further in the tank so I don't have to top off often as I run an open top. Any thoughts?

 

[Wy Renegade]

What happens is the spray bar ends up out of the water and starts spraying water across the tank to the opposite wall. as the water splatters on the opposite wall, much of it is thrown into the air, allowing it to evaporate or fly out of the tank. The emptier the tank becomes, the worse the situation gets. This is particularly a problem in small tanks where the opposite wall is only a short distance away from the spray bar. So long as the spray bar is always submerged, its not an issue. I've personally emptied most of a 20gal long onto the floor in this manner using a maxijet 1200 to power a DIY 1/2" PVC spray bar.

 

[meegosh]

Okay, that makes a bit more sense. I was picturing water shooting up into the air out of the spray bar. I think that is even more of a reason to make one that is adjustable. If I know I am going to be gone for a while I could lower it and not have to worry about it coming out of the water. I'll have to play around with it... I'm thinking some type of flexible tubing that I could make a U with but could also straighten for the extra depth needed.

 

[Wy Renegade]

Curious to see what you come up with, mine was simply a piece of vinyl tubing ran to a PVC spray bar. The spray bar was attached via suction cups, so could be moved higher or lower in the tank as desired. Since it was running via the maxijet, everything was internal in the tank.

 

[meegosh]

I'm thinking magnets sealed in silicone to hold the spray bar in place. I'll have to fiddle with it thought to see what works. We have all types of super strong magnets at work but I'm afraid I won't be able to place them on carefully and they will just slam together and smash the glass.

We'll see though. This is going to be my project this weekend. I'll be sure to take plenty of pictures.