The "Flow vs. Water Level Height" Factor: Are HOBs Right for my Goldfish Tank?

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ArtesiaWells

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The "Flow vs. Water Level Height" Factor: Are HOBs Right for my Goldfish Tank?

I have noticed that depending on how high I keep the water level in the tank, the HOB filters' return flow is affected -- this seems obvious, but let me explain the context in which I'm thinking of this scenario:

It's really during feeding time in my tank that I take this into consideration; I notice that both my Aqueon QuietFlow 55 and AquaClear 110 HOBs produce a tremendous amount of current from their flow return stages, at times it seems too much for my four fancy goldfish to handle -- while they're not really of the "super exotic" variety with large, fragile egg-shaped bodies, my fancies seem to be "thrown about" when they approach the return flow from these filters, hunting for their flakes (or even just swimming by them). With the Aqueon, there is no "flow control" to adjust, thus the filter is always running "wide open," while with the AquaClear, as we all know, there is a "flow control valve" which can be set from minimum to maximum -- on my particular 110, for whatever reason, this "lever" doesn't make much of a difference in terms of flow if I put it on minimum or maximum. Right now, it's running real close to minimum output and the return splash is really large and aggressive, splashing into the tank with force that's making the plant nearby really sway and sometimes bend under its power...

When my water level in the tank is below the brim line a bit (i.e. not filled to the very, very top), the Aqueon filter delivers an aggressive ripple across the surface that is enjoyable to watch, but which also causes turbulence for the fish especially when they're eating...at this water level, the AquaClear 110, meanwhile, delivers a steep "drop" of a splash return; if I fill the tank up pretty high, what happens is the Aqueon suddenly runs with almost NO current as the "ripple" across the surface disappears and you can hardly tell the filter is on, while the AquaClear delevelops the "ripple" across the surface...so it's like the opposite takes place...

I have also noticed that when the water level in the tank is pretty high up, the bubbles that are snapping from the two bubble bars in the rear of the tank at the surface are causing water to run down the back of the glass, leaving nasty looking water scar run marks; when the level drops lower, the snapping bubbles stop causing this -- but then the FILTERS begin their "too aggressive of a current" return flow...

What is the happy medium here? What is the best way to manage the water level of the tank, overall, while making sure the HOBs are delivering the "right" kind of return flow? If my goldies are being affected by the aggressive current of these filters, what should I do? Look into "baffling" their flow at the output with cut up pieces of soda bottles, as I've read about? Or should I keep the water level in the tank high enough so that both filters have a somewhat reduced output?

With the Aqueon, this rift across the surface it creates looks great -- but it seems way too "powerful" for the fish to deal with; likewise for the AquaClear's "wave" that's created when it returns water to the tank...if I keep the tank pretty much filled to the brim, is it okay that the Aqueon doesn't deliver a "ripple" from its return flow?
 
Oh, additionally:

Would it make more sense, based on the more "delicate" needs of my particular fish, to switch to a canister type filtration system that won't "pour" a wave of filtered water back in to the tank like the HOBs do? I never considered a canister system, always preferring the HOBs; but now I'm beginning to think these things are just creating too "aggressive" of a current in the way they return water...
 
It's whatever you want. I keep my level high but remember you want some surface agitation.

Don't over think things so much. It's preference. You want a waterfall huge ripple effect then go for it. You want a quiet flow then raise the water level. Also of you lower the water level so you agitate the surface your allowing for more oxygenation.

Pretty much it...
 
Well, with all due respect, I don't think in this particular case "that's just it;" this is not a matter of my personal preference, but of what is affecting the fish -- the goldfish seem to be totally thrown about by the return currents of these filters, so I was wondering if just leaving the tank filled to the brim so that the Aqueon at least isn't pushing much water is the answer, or if switching to canister systems is better...

With Chichlids, like you keep, the situation is totally different -- those fish, from what I understand, are USED to strong currents and dealing with them; goldfish of the FANCY variety do not react the same way due to their delicate makeups...
 
Dino,

Do you have a video you can share of what your AquaClears look like running on your setup?
 
You could baffle one/both of the filters. There are a lot of DIY ideas out there for how to accomplish that.
 

Thanks; the problem with that video, though, is that I can't really make out what the actual return flow of the filters look like coming back into the tank -- which is my major issue I'm referring to in this thread...how "deep" or "aggressive" is the return splash on your AquaClears? Do you have any daytime pics of the tank full on from the FRONT to see the return splash aggressiveness?

Also -- what are your flow control levers set to? Seems like they're more toward the "slow" side...am I right?
 
You could baffle one/both of the filters. There are a lot of DIY ideas out there for how to accomplish that.

I figured that was the other viable option; using cut up pieces of plastic bottle and such...

These fish are just so darn sensitive to the return flow of these HOBs; they are thrown around when they pass them and I really feel bad when it happens; it's like they would rather have still, stagnant water to swim in, but we all know we can't give them that in an enclosed aquarium environment...:(

Filling up the tank to almost the very tippy top doesn't seem to be the answer, either, because then the Aqueon filter puts out no flow, though the AquaClear continues to ripple across the top...:banghead:
 
What's the deal with canister filtration systems? Do they cause the same kind of rippling current like the HOBs do? If NOT, does this seem like a sensible change to be made in my goldfish tank, given that they're sensitive to the current?
 
if you want to go canister, id go with a eheim classic 2215 or 2217 depending on budget for your tank, it has a high flow (lower then comparable canister filters) but with it you can drill holes into the spray bar to lower the flow to just a trickle if you want while not effecting the filtration capacity. it also provides excellent bio-filtration which im sure is important with gold fish as well as very good mechanical and fine particle filtration. they also have 0 pass through, so every bit of water that goes through the canister is getting filtered, unlike most other canisters with high flows, a portion of the water just passes through without being filtered. Plus with good maintenance they can last for years, and are nearly silent.

some say that priming the canister is a pain, however it takes me only 2 mins to prime mine, so if you do decide on it send me a PM and ill explain further on how to do it.

dont just take my word on it of course, do some research and see what is best, but when it comes to the eheim's take the "impossible to prime" reviews with a grain a salt, as they have no clue what they are doing.

forgot to add, that with pretty much all canister filters you can aim the output anywhere you want. Though during feeding times, i just turn my filters off so food is not getting pushed around, and once the fish are done eating i simply plug them back in.
 
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What size is the tank? Perhaps you don't need both filters, and do keep the tank filled. You probably don't need the air bubblers either which seems to be causing water to seep under thew rim.
 
if you want to go canister, id go with a eheim classic 2215 or 2217 depending on budget for your tank, it has a high flow (lower then comparable canister filters) but with it you can drill holes into the spray bar to lower the flow to just a trickle if you want while not effecting the filtration capacity. it also provides excellent bio-filtration which im sure is important with gold fish as well as very good mechanical and fine particle filtration. they also have 0 pass through, so every bit of water that goes through the canister is getting filtered, unlike most other canisters with high flows, a portion of the water just passes through without being filtered. Plus with good maintenance they can last for years, and are nearly silent.

some say that priming the canister is a pain, however it takes me only 2 mins to prime mine, so if you do decide on it send me a PM and ill explain further on how to do it.

dont just take my word on it of course, do some research and see what is best, but when it comes to the eheim's take the "impossible to prime" reviews with a grain a salt, as they have no clue what they are doing.

forgot to add, that with pretty much all canister filters you can aim the output anywhere you want. Though during feeding times, i just turn my filters off so food is not getting pushed around, and once the fish are done eating i simply plug them back in.

Thanks for the info; I was really concerned with the flow return rates of canisters vs. HOBs because if the canisters deliver a more "gentle" return as opposed to the HOBs' "waterfalls," this may make more sense than an HOB for my goldfish...
 
What size is the tank? Perhaps you don't need both filters, and do keep the tank filled. You probably don't need the air bubblers either which seems to be causing water to seep under thew rim.

Per my signature, it's a 60 gallon Marineland; as for the filtration, sure, I believe I'm running a bit overkill on it with both filters turning over some 800-plus gallons per hour together -- but over filtering is suggested for goldfish and I wanted to cut down on tank mainteance a bit by overfiltering (I still do my weekly 50% water changes though and sometimes a mid-week 15 gallon change)...

When you say "do" keep the tank filled, I can do that -- but when I fill it up to the brim pretty much, the Aqueon filter appears as if it's not even running because the return flow "ripple" disappears, and this concerns me because I don't know if this is the way this filter was meant to run or if it's creating enough current even though I am running an AquaClear 110 on the other end AND two 18" bubble bars...

I don't want to get rid of the bars, as the fish really enjoy the bubble walls and highly oxygenated water is a preference of the rather demanding fancy goldfish...but, the seeping of the cracking bubbles at the surface towards the back causing the water to run down the back is getting REALLY annoying...
 
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