Goodbye HOB!

There seems to be a common theme here. And from the look of the tank in your first post, the water level is down a few inches from the top. That could be part of the problem.

The motors on hang on the back (HOB) style filters needs to be lower than the water level in the aquarium. If the motor is higher than the water level, there can be problems.

If you have a power failure, the motor will stop drawing water into the filter and the water level in the filter will automatically drain down to the water level of the tank. If the tank's water level is lower then the motor, the intake pipe will not be primed with water and the filter will not automatically refill when the power comes back on, and the motor will run dry.

External canister filters like Eheim and Fluval normally sit lower than the tank (although they can sit next to the tank) and are connected by hoses. If there is a power failure, the hoses remain full of water and the filter remains full of water. This means the motor and filter case are always primed and ready to start as soon as power is restored.

Have you had any power failures lately?
Very good points!
No power failure, and the water level was still above the motor, but this very well could still be the cause. Its an open top tank so evaporation is a pain in the butt with it. I have to top the tank off 1-2 times between my weekly water changes already.
That said, the water line is always 3 inches above the motor at the very least.
 
I don't like the new priming system Eheim, Fluval and a few other companies put on external canister filters. They cause so many issues. They really don't need it either, but companies being companies, they must upgrade, upgrade, upgrade. If they aren't stuffing about with it, they aren't happy.

The easiest and most reliable way to prime an external canister filter is:
Have the empty filter on the ground with the intake hose in the aquarium.
Have an empty fish bucket next to the canister filter.
Hold the outlet hose near the bucket.
Suck on the end of the outlet hose until the water starts syphoning into the filter.
Put the outlet hose in the bucket until water starts flowing out of it.
Gently rock the canister filter to remove air bubbles in it.
Put your thumb over the outlet hose to stop the water coming out.
Put the outlet hose in the aquarium wherever it goes. Make sure it's well attached.
Plug the filter into the power socket and turn it on.
 
No power failure, and the water level was still above the motor, but this very well could still be the cause. Its an open top tank so evaporation is a pain in the butt with it. I have to top the tank off 1-2 times between my weekly water changes already.
That said, the water line is always 3 inches above the motor at the very least.
Fair enough.

Either you got unlucky with your AquaClear HOB filters or Fluval has let their quality control go downhill. I had AquaClear HOB filters for years and never had an issue with them. They were super reliable and even after multiple power failures where the filters ran dry for several days, they still worked after I filled them up.

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You can buy clear Perspex from most hardware stores and cut it to fit your tank. This would give you a cover over most of the top and reduce evaporation. Otherwise get a coverglass cut to fit.
eg: if the open section is 18 inches and the filter sticks into the tank 2 inches, get a coverglass that is 15.5 inches.

Or get a normal cover and just rest it across the middle support strip (assuming it has one).
 
My Aquaclear50 is 7 years old and still runs great. Does sometimes need manual priming after a water change. My Penguin 200 is running great after 6 years of use. I use sponge and floss in it instead of the cartridge. Both are very easy to service.
 
Fair enough.

Either you got unlucky with your AquaClear HOB filters or Fluval has let their quality control go downhill. I had AquaClear HOB filters for years and never had an issue with them. They were super reliable and even after multiple power failures where the filters ran dry for several days, they still worked after I filled them up.

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You can buy clear Perspex from most hardware stores and cut it to fit your tank. This would give you a cover over most of the top and reduce evaporation. Otherwise get a coverglass cut to fit.
eg: if the open section is 18 inches and the filter sticks into the tank 2 inches, get a coverglass that is 15.5 inches.

Or get a normal cover and just rest it across the middle support strip (assuming it has one).
Its a bowfront, makes it a PAIN to find something transparent to use as a hood but able to be cut to shape too.
I'll have a look for that stuff at the hardware store, may be something to work with. Acrylic sheets are too tricky to cut since our stores won't cut them for us anymore lol


I'm thinking I just have poor luck with any HOB because I've had issues with the Topfins too. Ugh the constant grinding sound of the sand in the motor drove me nuts and the shape sucks I find. Longer vs deeper, if the media in the first side gets dirtier, it stops flowing to the other side as well, but if you dont put the sponge on the side closer to the impeller, it doesn't filter nicely into the tank.
Unless you stick with cartridges, but I just do sponge media.

I'm tired of testing my luck with filters and tired of wasting money on them, so ill buy something meant to last longer. The AC70 that went today was not even a year old.

I took the motor off my working AC50 and put it on the AC70 and the 46 has a working filter again, and the 55 has a new canister in the place of the AC50 it had.
 
I'm tired of testing my luck with filters and tired of wasting money on them, so ill buy something meant to last longer. The AC70 that went today was not even a year old.
It's still under warranty then. I'm pretty sure they have a 2 year warranty now. I would send it back and get it replaced. Get a canister filter too but get this one replaced under warranty and keep it as a spare.

According to Hagen's website (see link below), which I just googled, they have a lifetime warranty on non wearing parts, so the motor should be covered on all your AquaClear HOB filters.

If you still have the receipts, I would take the ones with the stuffed motors back and have the shop send them off to their suppliers for repair or replacement.

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Perspex is often sold as acrylic sheeting. You can buy it from craft shops too but hardware stores are usually cheaper. You might even be able to get it online. It can be cut with a hacksaw with a fine tooth blade and use a file or some sandpaper on a sanding block to smooth the edges.

Try to buy 3, 4 or 5mm thick Perspex because the thicker stuff doesn't sag as much, and cut a couple of long pieces about 1/2 inch wide to glue on the main sheet to reinforce it some more. Perspex can warp and sag if it gets hot and thicker Perspex is less likely to do this and the extra strips (ribs) will also help reduce its sagging.
 
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The Aquaclear filters now come with a lifetime warranty so hopefully they can send you replacements for needed parts. A glass shop should be able to cut the plexiglass to shape for you. Or you could do it yourself with a fine toothed jigsaw.
 
Ive come close to cling wrapping it lol

Ive tried a saw with the acrylic, it broke it badly lol maybe best left to a professional. I think another suggestion was polycarbonate.

As for the warranty, I gotta dig through my pet store receipts in my email. I'm sure its listed somewhere in there. But yeah will be looking into the warranty. I'll have trust issues but spares don't hurt.
 
If the acrylic broke when you were cutting it, then either the acrylic was thin or the saw teeth were big and course. You want a fine tooth saw like a hacksaw designed to cut steel. They have very fine teeth and it will go through Perspex like a hot knife through butter.

You can also tape the Perspex to a thin piece of plyboard and cut through both materials at the same time. The wood helps prevent the plastic cracking as much.
 
Precisely right.

this material can be cut with most fine toothed saws, powered or not.
We recently finished building a green house with acrylic triangle shaped windows. Good news is that I kept a couple sheets to build a clear lid for both tanks.

if you end up cutting with power tools, make sure the teeth on any blade are sharp, if they are not, they will melt their way through the material instead of cutting, and you will need to go back and either cut again, or snap the piece of and scrape away melted plastic.

can be done though with very little chip-out.
 
with a proper cutting tool, you could even use a dremel to cut it.
 

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