Reducing flow in HOB filter

I've been reading a little lately on methods of reducing output flow in a HOB filter. I have a 10 gallon planted cherry shrimp tank that has a HMF and a Fluval C2 on it. The output of the C2 is a little strong, and I've seen several methods online of how to help with this. I don't really want to use the plastic bottle method, as it looks a little junky, tends to fall off, and there are reports of plastics leaching chemicals (not sure if that's true but don't want to do it anyway). I've also seen people cut intake sponges and put them over the output area. I did this, and it stays on great. It should provide a little more biofiltration and feeding surface area for my shrimp too. The C-series HOB filters from Fluval have pretty good overflow protection, but I just wanted to show a couple pictures and see if anyone thinks the overflow could be a problem. Let me know what you think.

The first photo shows the completed set up. You can see the water going around the sides of it (it's not a perfect fit but good enough). You can also see a little water overflowing around the intake tube, although this is not uncommon. I took the top off, and you can see that the little area with the Bio-Screen over the bio-media basin is full and flowing a little backward below. This should send it through my area that has some Purigen and then through my Seachem Matrix. This aquarium is at my office, so I'm not present on weekends and overnight, so I need to be absolutely sure I'm not setting myself up for a leak.

If you're not familiar with these filters, the front end is almost an inch lower than the back and there are overflow channels, so I can't see how it would leak. I suppose I could worry about it burning out the motor, but I don't think that's likely as there's not much water going backward and most of the overflow is just running back into the tank. It does make the little button that tells you to change the mechanical media useless, but I don't pay attention to that anyway and just change it monthly. The filter is leveled correctly as well.

 

You can replace the impeller with one from a lesser model if you want to directly reduce the flow. If your filter has enough height from your tank you could also lead an airline tubing from filter basin to tank and use it as a straw

 

For the cost of rigging up some kind of DIY fix you could just buy a cheap Topfin HOB. You can reduce the output to almost nothing by turning a knob and they're easy to mod. also will survive a nuclear war. To be clear tho this is the only Topfin product that I will ever recommend or use lol

 

I have to think as long as the overflow section isn't blocked water is not going to go anywhere other than back in the tank. I've done the same thing with a piece of foam on the filter running in my pleco grow out tank. I run a cascade 300 on a 12 gallon tank. I keep it turned up to full power. The foam attached to the outflow slows the flow enough to keep fish from being tossed around and yes, a great place for bacteria.

 

For the cost of rigging up some kind of DIY fix you could just buy a cheap Topfin HOB. You can reduce the output to almost nothing by turning a knob and they're easy to mod. also will survive a nuclear war. To be clear tho this is the only Topfin product that I will ever recommend or use lol

There was no cost. I already had the prefilter sponge, and I like my C2. It's more customizable than a lot of HOB filters, although I know people here love the Aquaclear line. I'm not looking at changing filters, I just wanted advice on whether you thought the sponge being there would cause any troubles. I can't see how it could, but a few weeks ago I had a canister filter fail with it's side latches breaking and siphoning 50+ gallons of aquarium water all over my family room carpet. I'm a little more leery of potential flooding these days than most.

 

There was no cost. I already had the prefilter sponge, and I like my C2. It's more customizable than a lot of HOB filters, although I know people here love the Aquaclear line. I'm not looking at changing filters, I just wanted advice on whether you thought the sponge being there would cause any troubles. I can't see how it could, but a few weeks ago I had a canister filter fail with it's side latches breaking and siphoning 50+ gallons of aquarium water all over my family room carpet. I'm a little more leery of potential flooding these days than most.

Sorry I should have read the whole thing, its fine but make sure to clean the sponge regularly. Might be different on the output but those little sponges like to accumulate mulm inside like crazy

 

Sorry I should have read the whole thing, its fine but make sure to clean the sponge regularly. Might be different on the output but those little sponges like to accumulate mulm inside like crazy

Yeah, this one used to be on my intake until I got one that was a little coarser. I'm hoping that it won't clog as quickly since most of the water will be coming out of the filter.