Connecting a tidal 55 to an undergravel filter in a 29-gallon tank

[aquascaper]

My logic for this project is pretty straightforward - I always vacuum the gravel when making water changes, so cleaning a gravel filter doesn't add any extra work. But Aquarium Science says I shouldn't vacuum. Either way, this setup now gives me the best of both worlds: a low-maintenance undergravel filter with a huge bio and mechanical filter, and I can use the Tidal filter basket for whatever I want.

I agree with Aquarium Science on this one - the arguments against UGF when using gravel substrate just don't make sense. Fine grain sand vs gravel is a different topic, though.

The good news is that the water intake tube fits perfectly inside a piece of 1" PVC pipe - makes this project a breeze. The bad news is that the inside dimension of sch 40 PVC pipe isn't standardized, so take the intake tube to Home Depot to make sure they fit. To make a DIY UGF filter, all you need is a 1" PVC pipe, 1" coupling, 1" to 1/2" bushing, and a 1/2" tee.

I think it's a good idea to only use perforated pipe on the blue pieces to get a more even flow, but that's just speculation. Long-term, the screen material might not be the best idea - it could get plugged up. Only time will tell.

I did it the hard way, connecting the 1" pipe to a small PVC box. The 1/2" PVC pipe is connected to the box. On my tank, the Tidal is mounted on the side, and the long-term goal is to have real plants along the back and side. The gravel you see is actually Eco-complete with a thin layer of gravel on top. There's 2.5" perforated pipe buried in the Eco-complete, and I wrapped screen material around this pipe. The idea is to create a slow flow of water through the planted section, which won't be vacuumed.

You can't see it here, but screen material covers the entire bottom. The round 2" piece of pipe is for another plant - a planter box. I used my table saw to cut the holes, but you can just drill them instead.

The final results are pretty great. I did a simple water flow test with the Tidal connected to the UGF vs unconnected, and I didn't notice much difference in flow. I did block the skimmer water intake on the bottom with silicone, though.

I'm really happy with this project. Being semi-retired, I need aquariums that can run with little supervision for a couple weeks at a time. I can use the Tidal just as a water pump, and this should be a very reliable system requiring little maintenance. I think this is a better option than using power heads - I can still use the Tidal as a filter.

Next mod for this system is an effective way of putting Polishing Felt Filter Pad 100 Micron in the Tidal filter chamber. I was looking at an air filter with a zig-zag pattern - it doubles the surface area of the filter material. How can I do the same with the felt polishing material?