The Puffer Forum

I currently have a single F8 in a 30 gallon long with a pre-filtered bio-only canister as well as two pre-filtered Maxi Jet power heads to provide mechanical filtration. The tank is basically set up as RTR detailed in a post here a few years ago. I know the old man doesn't post here anymore but I always found his expertise and advice to be concise and insightful. That being said, the tank upkeep even though simple, has been a little more taxing than I would like and I'm looking for a way to cut down on maintenance time while still keeping water quality high.
I came across the instructions for RTR's Over Engineered Reverse Flow Under Gravel filter on another site while I was initially setting up the tank last year, but some of the equipment he listed (Penguin reverse flow kit) was no longer being sold. While it takes some work to initially set up I really think this method would make a big difference down the line in maintenance time and effort.
I wanted to find out from someone in the know if Maxi Jet power heads can be set up to run an under gravel filter in reverse to the conventional way, i.e. flowing up through the substrate instead of pulling down through it. I've looked online for kits for the Maxi Jets for this purpose but have found nothing. Any info or suggestions would be welcomed.

I don't see how you'd get a powerhead to reverse.

I don't think that you would need the powerhead to reverse, you would just need to pipe the output from the powerhead onto the undergravel filter? As long as the powerhead does between 10x and 15x the tank volume an hour then the flow should be sufficient - not that I own a powerhead or an undergravel filter...

Wouldn't your maintenance be more taxing though because more detritus would be pushed up into the water column to clog up your pre-filters?

Pufferpunk wrote:I don't see how you'd get a powerhead to reverse.

Ilive has the idea PP. The power heads themselves don't flow in reverse but the under gravel filter does flow in the opposite direction than originally intended. So, from the pre-filtered intake of the power head then to the output and down through the riser pipe of the UG filter, down to the bare bottom of the tank and up through the filter plate and RTR's specified media setup and finally up through the substrate back to the pre-filtered intakes.

Ilive, from browsing through more than a few of RTR's old posts the idea is yes, the detritus gets picked up by the pre-filters, but those are rinsed with tap water/replaced with spares weekly. The setup also calls for 2 additional internal filters (Fluval) to control directional water flow and increase circulation and mechanical filtration. The concept is to have the filter media under the substrate and the substrate itself as the bio filter while the power head intakes and the internal filters serve only as mechanical. These mechanical filters would not clog because they would be cleaned/replaced weekly whenever water changes are done (or perhaps more frequently if needed).

It would be very quick and simple to shut down power to the tank, remove and replace a few filter sponges, vacuum the substrate during the water change and refill the tank. Because of the flow of the water up through the substrate, detritus would not settle into it and would be easily removed by light vacuuming. Also, because of the amount of mechanical filtration in the tank, the bio media and substrate would not clog. In addition to keeping water quality high, the flow of water through the substrate would also optimize the stability of pH, as the water flow would keep the amount of dissolved aragonite (in my case of substrate) high. RTR details keeping several tanks with different species of fish running for 15+ years and never having to fiddle with the UG portion of the filter. The idea of that amount of time savings through ease of maintenance is mind boggling.

I hoped that there would be info available on adapting currently available power heads to the riser tubes of the UG filter. It seems as UG filters have fallen out of popularity in favor of HOBs due to the common problem of UG filters clogging etc, while being used in their conventional set up, there just doesn't seem to be much info on these types of setups. I figured if there was anywhere with people who had some experience with this type of setup it would be here.

Liquid88 - if you have an aragonite sand substrate then surely you won't be able to use an UG filter because the substrate wouldn't be heavy enough to stay on the bottom?

What makes your current maintenance regime taxing?

I don't want to sound like I'm knocking your plans, I'm just interested.

Aragonite works because of the grain size of the sand and the fact that the tank is decorated with mostly dry rock and a few plastic plants. I use Caribsea Special Grade Reef sand that's between 1-3mm. It's the substrate reefers often choose for use in high flow tanks. The particles are fine enough that they still look like natural sand, but are heavy enough that they don't get blown all over the tank like sugar-sized sand would in tanks with high flow.

Additionally, RTR's method calls for using layers of bonded fiber pad, egg crate lighting diffuser and fiberglass mesh which also prevent sand/gravel from falling through or getting under the UG plate. The fiber padding also acts as an additional bio-filter and the sum of the layers help diffuse the flow of water up through the substrate. There wouldn't be areas of the substrate where sand would be moving about due to the grain size and the diffused flow.

The current setup of the tank is RTR's other common recommendation. It consists of a pre-filtered Eheim canister that contains only bio media (bio balls/ceramic noodles) and two internal filters which, in my case, are pre-filtered power heads. The method calls for weekly removal and rinsing/replacing of the pre-filters and vacuuming gravel during water changes (easy). Monthly the canister filter is back flushed by attaching a Python water changer to the inlet pipe, which draws water in through the outlet spray bar and removes any fine particles that may have settled in the canister (easy enough, but annoying and sometimes messy). Once or twice a year the canister must be broken down to clean the impeller housing and hoses (labor intensive, but not done often).

The RFUG method to me, while requiring more setup, would be much easier to maintain long term than the bio-only canister method.

The questions are quite welcome. I know everyone here wants to help and offer suggestions as much they can. I just miss the old man's input on here sometimes and in my case it would be invaluable. The method is something he thought up after all lol.

Yeah, I have tried to contact him by email. I hope he's OK.