Trickle filter question

[Blackwater Aquaria]

I would like some feedback about drilled tanks vs. overflow box system with no drilling. Thanks Mike

[Tropical Haven]

All personal preference, drilled tank is quieter and overflow is noisy. Both do the same job, it all depend how you want to do it.

[Elite Aquaria]

Mike,

I like to drill all my tanks. My uncle had an overflow box and man did it make alot of noise...

Dan

[Polar_Bear]

Other than being noisy, with overflow boxes you always have the chance of them losing syphon and so they can be a bit catastrophic as far as losing water. Drilled tanks don't rely on a syphon so the chances of a mishap are MUCH less.

[tcfish]

If you have a way to go a drilled tank is the way to go but like anything else it all depends on your set up and how you plan on going with it

[mikesmac]

Hi Mike,

I have some tanks that are drilled ....with bulkheads and built in overflows and some tanks with add-on overflow boxes and both can be just as noisy depending on the water flow through them. I have pretty much eliminated any noise however by installing valves on the lines running to the filter to keep the water levels at a height where they don't make any noise. It does take some adjustment to get the flow rate right and may also vary depending on how clean prefilter materials are, but the valves do eliminate the noise problem for the most part.

One other thing... my tanks with the overflow boxes....When filling them back up I block the return line in the overflow box and fill the tank right to the rim. Then, if for some reason the box did lose it's siphon (which hasn't happened yet..knock on wood) ... even if all of the water gets pumped out of the filter sump the tank won't overflow and most pumps won't pump "that last little bit" of water out of the sump so it goes up the return line and back down and back up..so the pump doesn't really run dry potentially burning it out....unless you have check valves on the return lines...then it may be a problem.

I've found the bigger problem to be with drilled tanks as it requires the sump on the filter to be large enough to handle all water that drains in the event of a power failure. I've had to replace some filters that were "supplied" with tanks because they weren't big enough unless the water level in the tanks were always run low.

Mike

[Apistomaster]

One of the things that can make a difference between a quiet or a noisy overflow or pre-drilled drainage system is if the water is dropping vertically it tends to make noise. If the drain hose is flexible and arranged to have parabolic curves before it enters the wet/dry filter sump it tends to run silently.

I won't use any HOB over flow without also using an Aqualifter Pump to continuously remove air bubbles as they occur in the tube or C-siphon. These pumps allow overflows to operate at their peak design efficiency. Siphon bubble accumulation is inevitable unless they are prevented from accumulating with a water vacuum pump of some sort.

If I were setting up a centralized filter system for multiple tanks I would always go with a drilled overflow instead of an overflow box.
I only have my display tank equipped with a wet/dry so I am using an overflow C-siphon design box. It is rated at 600 gph but actually is handling ~850gph using the Aqualifter Pump. It is a modified Tidepool overflow box. The flow control rod has been removed and both of it's drains are in use at all times. Both of it's drain hoses flow through compound recurves into a dual inlet and dual outlet manifold, then into twin wet/dry towers, silently.
The return pump is a MagDrive 9.5 pumping about 1 meter of head. The main pump is on a switchable power strip and the AquaLifter is left in an always on circuit. This prevents disaterous overflows after restart after power outages or during routine water changes. The overflow siphon circuit cannot be broken. Back siphoning prevention has been incorporated into the water return plumbing so a sump overflow is also impossible in case of power failure. Back siphon prevention is a passive design, not subject to mechanical failure.