Retrofitting HOB's - call me crazy, but I need ideas

[FMJnaX]

Yep, my crazy mind is working full force today so I'll take advantage of it.

I have both an AquaClear200 and a Penguin100 HOB. What I'm thinking of doing is retrofitting both of them with a deeper outlet to remove surface agitation. I'm removing surface agitation in preparations to more heavily plant my tank and I don't want my CO2 to escape as easily. Some of you may recommend a canister, but right now I cannot afford one so it's out of the question.

Currently, I keep my water level higher than the outlets, but this still allows enough ripple effect that I lose CO2; especially at the end of the week when evaporation has dropped the water level.

I'm thinking I can get some PVC piping or some form of flex-tubing to catch the water from the outlet and take it deeper in to the tank (1/2 way maybe?). I have a few mental dilemas that I can't seem to bypass:

1) Am I going to be able to find something wide enough to tack to the outlets to catch the water? I think PVC is made large enough, but I really want to go with something else

2) As mentioned above, I want to go with some sort of flex-tubing (like silicone tubing), but I'm not sure if anything is made large enough. Any suggestions on what I could use?

3) Can I taper the outlet down a bit or will it cause too much backflow? If I'm going with PVC (clear is expensive), then I don't really want 2 white 4" diameter tubes heading into the middle of my tank

4) What kind of paint would be safe to paint PVC that is in the water? Any at all? It would be nice if I could paint the PVC black or something.

I'm sure I'll come up with something else when I get home and start looking at things. Go ahead and call me crazy/stupid/whatever. I figure that it's at least worth a try.

 

[TankGirl]

I love how you are working with what you have, and in the process you can possibly develop something very cool. Necessity is the mother of invention, you know!

Let's say you extend the lip of the outflow of your HOB, moving it under the water. Unless I am not seeing this clearly the water will still strike the surface in the very same way, since there will be a water level inside the tube, and the water flow will simply strike this water level, though it is inside a tube. In my mind, the only way to prevent water striking the surface of the tank water is to create continuous flow between intake and outflow, but I can't see how you could do that with a HOB. Because the water has to "trickle" through filter media it has to "trickle" out again, and it is the trickle that is the problem.

Are you losing that much CO2? You may find that increasing the CO2 that you use in the tank will compensate for whatever might be lost with the HOB.

 

[FMJnaX]

I'm not losing much CO2 as long as I keep the water topped off; which is about 1 gallon every 3-4 days or 4-5 gallons every 7-10 days. I get minimal agitation and rippling. Because of this, it's not a top priority, but just something I would like to try. CO2 is at about 27 ppm, so I'm getting good levels, but I have to use three 2 L bottles (regulated with a crude Y valve).

I thought about the agitation and thought it would be better in a confined 4" diameter (in the PVC/tube). This would be less surface area agitated so I figured less gas exchange would take place. It would also give the rest of the tank a calmer appearance (another thing I was shooting for). At the same time, I guess the agitation may be more defined because it doesn't have the space to spread. Any thoughts on this?

Another thought that I just had, but probably can't even be done, is to angle the PVC/tube so that it gradually drops from the left side of the tank to the right. This will give less distance for water to fall, thus reducing the agitation inside the tube. It's hard for me to explain, but I'm getting a nice mental picture of it. Also, if I keep the water level above the stock outlet, then I will have even less agitation in the tube. I'll have to just experiement and see what I get.

Like I said, my crazy brain is in full force today.

 

[TankGirl]

What if you angled the water backwards towards the tank glass behind the lip of the HOB return? That way it would be flowing down the extension piece (no splash there) and flowing against the back glass into the water (very minimal splash). It would also keep your design compact.

 

[FMJnaX]

Awesome idea! Much better than having it flow from left to right. It would also reduce the material cost a lot. I'll have to think of a way to attach it all now. That may end up being the tricky part.

 

[TankGirl]

Good ole two-part epoxy should do the trick. Once it has cured you do not have to worry about anything getting into your water.

 

[Zezmo]

I have a TetraTec 500 HOB filter. When I went planted I too wished to reduce the surface agitation. My HOB has 3 inlets back into the tank. 1 that uses a deflector to shoot the water along the surface, 1 that is just an opening that dumps the water straight down in to the tank, and 1 that also has a deflector, but it is the outflow to the wet-dry system.
I used the riser tubes and deflectors from my old UGF over the first two openings. This allowed me to put the outflow well below the surface. The third one, the wet-dry output, I was also able to hook up like this. But, it kept the wet-dry from working properly. I ended up just pointing the 3rd deflector backwards into my glass.
There is minimal surface agitation, but that corner has a strong current. As it turns out, my Bloodfins love the current and the whole school will zoom about and play in it.

 

[wabyrd]

If you're not losing that much CO2, is all that work necessary? I've got 2 Emperor 400s on my tank and sure there's a little surface agitation, but there's enough CO2 to get the plants to grow like crazy. I do inject with a tank, but my 5lb tank lasts over a year and only costs about $30 to refill.

 

[greenmaji]

I am thinking of using a 3/4 inch pipe and cutting it in half long ways and attaching it to direct the flow to the back of the tank.. im pretty sure this is something like what TG was saying.. gluing it with some epoxy on the ends to the side lips of the output of the filter would work.. I would think..

 

[FMJnaX]

I think I may give this a shot and see what happens....

http://www.plantedtank.net/forums/showthread.php?t=18709

 

[greenmaji]

I think I may give this a shot and see what happens....

http://www.plantedtank.net/forums/showthread.php?t=18709

that looks like a good solution.. better even.