Powerhead failure     12/5/13
Hey there Holly again,
While cleaning my tank this morning and doing a routine water change, one of my powerheads quit, and the other no longer spits out bubbles.
<Ahh... likely the venture (air intake) line is occluded, or the impeller isn't producing sufficient pressure at the junction to entrail air>
Water is flowing out the outtake but no more bubbles. I don't have any other aeration (i.e. airstones) . Is this a big problem?
<Not likely; no.>
I'm planning to get a new powerhead tonight after I get paid, but while I'm buying should I get a pump & airstones?
<Again...>
Just a reminder 55 gal. Marineland 400 Bio-Wheel Power Filter the 660 powerhead that's working (sort of) & the 550 that quit. Still no protein skimmer.
Holly
<I'd remove the powerhead, the tubing... and soak all in white vinegar for an hour or so, rinse and re-try. Bob Fenner>
Re: re: Powerhead failure   12/8/13
Thanks for the quick reply. I got a new powerhead. They're attached to my undergravel 1" tubes no air lines or air pump with air stones at all in the tank.
<Ahh! I'd add another "reason" for their possible failure here, given your mention... IF the gravel bed is "too clogged", the restriction on the powerhead intake/s can be trouble... these are centrifugal devices...
should not have restriction on their intake/s>
I use them for the undergravel filtration. They are both Aqua-Tech power heads. The new one is much quieter and producing lots of bubbles so I think the motor was going out of the old one. The other one is still no bubbles and again only attached to the 1" tube going into the undergravel.
<... I'd vacuum the gravel thoroughly>
Should I get the airstones and air pump?
<.... see WWM re aeration... testing for DO>
 I'm curious if this is why my nitrates continue to test zero?
<And re NO3... may be test kit issue; perhaps metabolism in/of the system...
all this is gone over and over, archived on the site>
 I had a brown (diatom) bloom that has cleared up since my last water change/cleaning. But again I have tested daily for weeks and my nitrates always test 0...
Any words of wisdom???
<Keep reading. BobF>
Holly

Removing an undergravel filter plate    8/31/11
Hi,
<Todd>
I have a 75 gallon saltwater (fish) tank. It has been setup and running for 8 years with a undergravel filter plate (don't laugh), two canister filters and two power heads for the UGF. About 3 months ago I removed one of the canister filters and replaced it with a 20 gallon refugium. I have been thinking about what to do with the UGF's and want to know if/how I should remove them or just keep them?
<Could remove... or just pull the water moving mechanism, ignore the "mulm" underneath... IF pulling could just lift out/over the rock, decor and scoot the substrate over (vac first!) and lift one plate out at a time... IF so inclined, you could do the ultimate, removing the livestock, rock, decor, most of the water, and scoop out the gravel/substrate, remove the UG plates... do summat of a cleaning, rinse the gravel, return all in order... and trust in your refugium to supply bio-filtration... The options/choice is up to you. Bob Fenner>
Thanks for your help.
Todd

SW UG Filter question, 2/18/10
Hi, Folks.
<Hello>
I see that you are continuing the excellent job of helping people.
<Thanks>
I am planning a 90 gallon marine aquarium. Lots of thinking and reading to do, and the WWM site has been a tremendous help, as has a good re-reading of "The Conscientious Marine Aquarist".
<Great>
One question to which I do not seem to be able to answer, though, is whether it makes sense to include an undergravel filter in the system. I am planning to have the following in the system:
- overflow box to feed a sump
- sump with AquaC protein skimmer
- large canister filter
- 90 or so lbs. of live rock to initially cycle the system
- 20 or so lbs of live sand mixed with the normal stuff (~4" total) to initially cycle the tank.
<Sounds nice.>
I still need to figure out what else I need in the sump, but those are, I believe, the basics.
I still have a lot of reading to do on the WWM FAQ pages.
Is an undergravel filter redundant or a good idea in this setup?
<I would consider it unnecessary and a bit problematic since it will trap detritus is a difficult to clean place, I would skip it.>
This will start as a FO system and progress through FO with invertebrates and eventually a live reef system (but that will take a year or two, I suspect).
Cheers
Dave
<Good luck with the new tank.>
<Chris>