Flow in your tank

[RTR]

Turnovers, or more accurately, the current in the tanks varies tremendously among my tanks. I set tanks for the fish involved. My river rapids tanks ran >>20x turnovers, my heavily planted DP tank runs a rated high turnover, but in sensible current it is a lot less - it has over-powered RFUGs which are undetectable to the fish, just a couple of smallish internals provide flow and current to the fish and plants.

I don't see any association between algae and current at all, provided there is enough current to provide the plants with nutrients which are added for them.

 

[TPIRman]

The flow or amount of filtration has little to do with the amount of algea.

I don't see any association between algae and current at all, provided there is enough current to provide the plants with nutrients which are added for them.

There's actually an interesting thread over on Aquatic Plant Central right now about water flow and plant growth/algae, with the general consensus being that current is underrated as a factor in planted tanks. One member has posted a picture that demonstrates this in stark fashion, albeit anecdotally. Worth a look for planted-tank owners who are concerned about water flow:

http://www.aquaticplantcentral.com/forumapc/showthread.php?t=10240

 

[ChileRelleno]

I've two AC500/110's modified with Bio-Wheels on my 75gal, thats 1000gph or 13X+ hrly.
I've 10gal's with AC300 & 200's, 20 -30X's hrly I just didn't want to buy smaller filters when these were already sitting around.

 

[patoloco]

I keep my 220 gls tank with a turnover rate of about 6 times an hour. The return has a big-holed sprayer bar directed toward the back glass to reduce the current in the tank, so the fish will not be dragged against the glass and will be able to swim around.

This rate was measured filling a 5 gallon bucket with a stopwatch at hand.

Also, this setup creates a strange whrilpool like current near the overflow that drags all the dirt and uneaten food to a single spot in the bottom. It's really easy to clean, thought that particular spot look terribly ugly.

 

[patoloco]

Another thing: is the nitrification procces afected by the speed water flows trough the filter media? Ar a high water flow, will bacteria have enought time to do its work?

 

[RTR]

Flow through a filter and current in a tank are completely distinct subjects, no relationship required. I think that it would be difficult to have so much flow that biofiltration could not occur, and it certainly does occur in all commercial filters I have tested.

I am a fan of and a user of current. But the thread over at APC is really addressing the issues of currentless tanks, or tanks with dead spots. Anybody who has ever looked at my tank specs would realize that such is not going to happen in my tanks. Even Diana Waldstad's filterless tanks have current, generally pretty hefty current.

 

[PumaWard]

This is interesting,


RTR, or anybody who would like to answer... I always had difficulty with spot algae growing on my anubias and this brownish algae on my ambulia. I started cutting back on my filter running; it went from 14 hrs / day to 1-2hrs/day and I noticed a considerable cutback on algae accumulation... and it has finally started to die off and my plants look the healthiest they have in a long time. I don't inject CO2, so I don't know if maybe the filter was degassing the only CO2 in the tank. What do you think?

 

[TPIRman]

I am a fan of and a user of current. But the thread over at APC is really addressing the issues of currentless tanks, or tanks with dead spots. Anybody who has ever looked at my tank specs would realize that such is not going to happen in my tanks.

I wasn't really commenting on the state of a specific hobbyist's tanks as much as I was calling into question the general assertion that there is no relation between current and algae aside from proper distribution of plant nutrients. I'd respectfully argue that things are more complex than that, which is why I found the APC thread interesting, as the folks there are in fact trying to expand on the widely accepted notion that it's best to avoid dead spots. But people should take a look at the thread for themselves if they're so inclined.

I do agree that discussion of flow rate (in terms of turnover frequency) and properly distributed current are quite separate.

 

[RTR]

For me the best defense against hard green spot on Anubias (or glass) is keeping phosphate up to 10% of nitrate levels or a bit more, but never less. As I use lots of A. nana, that is very important to me - it is my main carpet plant in multiple tanks.

 

[pikwik]

AC 500 and HOT Magnum 250 on my 55g at the moment. Water is very clear and no algae is present. Though I'm sure the 50%+ weekly water changes I do have more to do with that than the turn-over flow rate.

I have an AC 300 on a 40g tank, and do 30% water change 2x a week. I have crystal clear water and have never seen algae in this tank.(7 months now)