As a preface, I've researched the absolute hell out of solutions for this, and just can't figure out where to go from here. Need some advice
So, one of the last times I went to the LFS, I was conned into taking home a large bagful of duckweed for my 55g. I'd always heard good things about it, in regard to helping regulate excess ferts and lowering nitrate levels. I had also heard the cons as in the inability to rid your tank of it, when you chose to do so.
I was running a Marineland Penguin 350 HOB filter on my 55. Hadn't even considered what this would do with the duckweed. Dropped in the duckweed and had a duckweed/confetti shower. Thought maybe it'd settle over time, that obviously didn't work. To solve this, I tried:
1. cutting out floating guards to go around the output splash from the HOB
2. tried raising the water level so that water just pushed out of the HOB
3. tried making a guard to corral the duckweed on the other side of the tank
These all worked temporarily, but never seemed to maintain. So after alot of reading and research on solutions for this, I switched to a Powerhead instead of my HOB. The powerhead I got had a prefilter attachment. This worked for about a day, then the next morning I awoke to the prefilter intake completely covered in duckweed and putting out nothing.
Started researching again.... found out I should try a sponge prefilter intake. I couldn't find one that would adapt to my powerhead, so I got some open cell foam from an Aquaclear sponge replacement. Cut it up into a good fitting rectangle around the prefilter intake. Worked great for about 3-4 days and was building some good bacteria on it, but this morning I checked the flow from the powerhead, and it wasn't putting out anything. I took off the intake prefilter, and the output increased, but I already think there has been damage done to the powerhead.
So my dilemma:
1. Take out all of the duckweed and depend on my 3 water sprites and 2 anacharis for absorbing excess nutrients, and be able to put the standard prefilter attachment back on (thus maintaining patent output flow and not burning up my powerhead)..... Or
2. Trying to find another solution whilst keeping the sponge prefilter intake from ruining my powerhead.
My main concerns are losing the duckweed's "buffering" capability by removing all of it (or atleast trying to)..... or on the flipside, removing the sponge prefilter intake and not really having a filter medium for keeping good bacteria growth. Has anyone else found a way to keep the sponge over the prefilter without burning up the powerhead?
Any thoughts would be great... and sorry for the extra long read