Ideal Turnover Rate?

[jschall]

MeAko, so you are suggesting that at 1~2x turnover, the the large pieces of waste that come out of those large fish make it all the to the intake?

What would happen if you stopped doing any manual cleaning and stopped doing water changes for a month... would 1~2 times turnover still be enough?

If the reduced turnover only maintains excellent conditions with manual assistance, I think that is an important factor...

I kept a 6' round 300 gal Rubbermaid for several years and with it I learned that you can get away with things (both filtration and stocking) in a very large 'tank' that you just cant get away with when scaled down to a typical sized aquarium. But even with that in mind... 1~2 x turnover isn't very much...

Especially since your flow pattern doesn't promote circular motion. It seems any waste dropped in the right half (per the picture) of the pond will just sit there... unless the additional current provided by the fish swimming moves it to the intake.

I also wonder if you should add in the water movement made by those huge fish swimming around

Please do not take this to criticize your tank at all. It's a beautiful impressive monster of a tank. I just think it is the "exception", not "the rule"... and thus doesn't serve as a good example in this 'debate'...

I have 2 6" turtles in 110 gallons with 2x turnover. I never see waste sitting on the bottom.

I have a betta and snails in a 3 gallon tank with 30gph (10x turnover) and snail poop gathers on the plants, driftwood and gravel.

 

[aquaventions]

I was doing 1x for a couple of months and only did 2x when I added a Ray. My nitrates are 5-10ppm. Water looks mighty crispy to me...not too shabby for 2x.

If your fish are healthy and happy, there is no need to change anything. Something to keep in mind though is the dissolved oxygen content which you cannot see.

 

[CHOMPERS]

I just think it is the "exception", not "the rule"... and thus doesn't serve as a good example in this 'debate'...

Actually MeAko is presenting good evidence even if it isn't what you want to hear. You don't end up with scientific results by when you pick and choose your evidence. When you do, you end up with results that back up your claim or assumptions but the results don't really prove anything. It just says what you want it to say. MeAko has evidence that shows that the accepted "facts" that are incestantly repeated on this forum are false.

And I side with MeAko because I have had and have tanks of both extremes. I have converted high turnover tanks to unpopularly low flow rates, and with good success. High turnover rates account for not much more than that of a 'Richard' swinging contest.

 

[MeAko]

MeAko, so you are suggesting that at 1~2x turnover, the the large pieces of waste that come out of those large fish make it all the to the intake?

Hi nc_nutcase. Your post is a good one--and allows me to add the details and qualifications so that people also gain a deeper understanding of the effort needed to keep these things running well. Let me get into more details:

I forgot to mention that I added a pretty sizable powerhead and realized now that it is not in the picture. Ever since I added the powerhead, I hardly ever need to do any manual netting out of poop, the only time I net poop is when I see the actual event itself, then I hurry to get the net before one of the kois or sharks eat the poop, it's a race.So, yes, all the monster sized poop eventually get to the intake one way or another. Water's even crispier now that I added the bulkhead.

Additional things that I need to mention that make 1-2x turnover rate work:

• My powerhead which creates undercurrent and brings dirt and stuff to where it's supposed to go.
• Removing all my substrate and tank decorations, effectively removing all crevices and space for dirt to hide.

• 50% WC weekly. Nuff said!
• Two MONSTER wet/dries, discussed here. I believe these wet/dries are very critical because the amount of mechanical and biological filter media that I can squeeze into all those crates is mind boggling. These things I believe do a spectacular job of polishing the water and maintaining my parameters.
• Not overfeeding, if there is any food left after 60 seconds, then that is an indication to me that I've fed a bit too much...hehe. One day a week fasting. As much as possible, hand feed so that everyone gets their fair share. Meat eaters eat every other day.
• I believe the fact that my pond is 1,175 Gal should also be an important factor in the analysis as water at that volume provides a lot of stability.
• I think my pond is also understocked; well, compared to some of the stocking levels here.

 

[dawnmarie]

Only dead fish go with the flow. Go Figure

 

[Toby_H]

Thanks for the added detail MeAko... You brought up quite a few details that I'm sure add up to a big difference...

And Chompers, I am by no means suggesting we remove evidence to alter the result... instead I asked that detail be added so we can properly analyze the situation and see it for what it truly is.

Details like, lightly stocked, no substate, no decor, 50% weekly water changes, additional water movement via powerhead, etc valid information that is worthy of being taken into account along with the filter's flow rate.

Also note my previous response had nothing to do with "more is better" or swinging anything. Instead I suggest that details matter and should be taken into account. I promote smarter filtration, not bigger filtration.

 

[MeAko]

My thoughts are simplistic:

The higher the turn over =
FASTER Ammonia and Nitrites are converted to Nitrates

How clear your water is, is generally a good indication that excess food and poop is hurriedly sucked into the sump to start the nitrification process. Lessening the direct exposure of the fish to the objects that excrete ammonia.

In general, most respectably maintained aquaria and ponds have 0 Ammonia and Nitrites. If your ammonia and nitrites are achieved at say 2x or 20x turnover, any x above it just helps with oxygenation and water current, that's all.

A high turnover of course still doesn't dimish the need for water changes, turnover and WC both are required of Monster Fish keepers to help achieve ideal water parameters.
​

 

[dawnmarie]

...Details like, lightly stocked, no substate, no decor, 50% weekly water changes, additional water movement via powerhead, etc valid information that is worthy of being taken into account along with the filter's flow rate.
Also note my previous response had nothing to do with "more is better" or swinging anything. Instead I suggest that details matter and should be taken into account. I promote smarter filtration, not bigger filtration.

I couldn't agree with you more and the points you make continue to illustrate the futility of attempting to answer the OP's original question. Asking anyone for the "ideal flow rate of any tank" is pointless. The question is unanswerable. Every tank is unique. I imagine the OP was sincere in wanting to sample opinions unfortunately the question is ill conceived.

 

[dawnmarie]

My thoughts are simplistic:

The higher the turn over =FASTER Ammonia and Nitrites are converted to Nitrates​

If this proves to be true then my limited understanding of the Nitrogen Cycle is incomplete.

Could you expand on this ?​

How clear your water is, is generally a good indication that excess food and poop is hurriedly sucked into the sump to start the nitrification process. Lessening the direct exposure of the fish to the objects that excrete ammonia.

I'm not sure I understand.The clarity of your water indicates how effective your mechanical filter is . The less effective, the higher the turnover rate would have to be to achieve clarity. The length of time your fish are exposed to Ammonia/Nitrites is determined by the Biological filters ability to convert ultimately to Nitrate. Nitrate remains until removed most commonly by water changes.I guess I don't see a direct correlation between turnover rate and the nitrification process.

In general, most respectably maintained aquaria and ponds have 0 Ammonia and Nitrites. If your ammonia and nitrites are achieved at say 2x or 20x turnover, any x above it just helps with oxygenation and water current, that's all.

I couldn't agree with you more. I may just borrow this quote.

A high turnover of course still doesn't dimish the need for water changes, turnover and WC both are required of Monster Fish keepers to help achieve ideal water parameters.​

So true