Undergravel filter...

[Walt]

Ok....
I setup my tank with an undergravel before i had really thought about it....
I know i could do a tear down n such... but, i had another thought....

Other then it not being ideal for plant roots, the other thing ive been worrying about was the air stones in the uprise tubes, stripping CO2 from the water once i hook up my co2 tank....
Soooo.. i was thinking, i could do 1 of 2 things...
1. Pull out the airstones n replace em with power heads....
2. Turn off the uprises during the day when injecting co2, then at night, turn off the co2 and turn on the airstones in the uprises.. my thinking is that would help add o2 back into the water at night plus more filtration would be kicking in over night....

Think the biological buddies in the under gravel would be ok with a plan like this?

i know pulling the undergravel out would be ideal, but im interested in hearing what you all think about these different ideas....
Plus ive stacked big river rocks on top of it on the back wall.....

Course, i could just pull out the uprise tubes n drop better substrate right on top of it...

Thanks! B)
Walt

 

[Walt]

bump....

ya.. i know.... UG filters bite....

but anyone have a 2 cents worth thought on this?

 

[IovaykInD]

Tear it down, not much to it.

Isaac

 

[zig]

Hiya Walt

Not really sure about this, but my 2 cents anyway, but hopefully others will reply.

Option 1 might work as long as the powerheads are under the water and not splashing the surface, but powerheads might cause a whirlpool effect and drive out the co2, so im not sure i guess it depends on how many powerheads you intend to use, powerheads can be used in planted tanks but they are usually used to supplement the main filtration, usually they are used in so called dead areas or areas of very little water circulation usually due to heavy planting, sometimes because of plants blocking the main spraybar people will use powerheads to create water movement, these so called dead areas are prone to algae particularily BGA.

Option 2 i dont fully understand because how will the filter work if you swich off the uprises during the day? so this i am not sure about.

People will often run airstones at night anyway and switch off their co2, to oxygenate the water and drive off the excess co2, if you do this you should turn the co2 back on 1 hour before your lights come on (and obviously the airstones switched off) to allow the co2 to build up in the water to a sufficiently high level, again this is quite common practice, you would probably need a solenoid on a timer for this unless you are there all the time.

You could always try option 1 when you have the co2 in place and running properly, you could measure how much co2 is auctually dissolving into the water, what type of reactor or diffuser will you be useing? if you found you were'nt getting sufficient co2 dissolveing into the water just up the bubble rate on the regulator and measure again until you have enough co2 in the water, you may use more co2 this way but at least it would work.

Or, well i think you know this one.............take it up and start again..........but i suppose you dont want to hear that one, anyway thats my 2 cents worth, but i know some people do use undergravel filters, its just they are not ideal, but hopefully you might get some ideas around this from the above.

 

[Walt]

Good 2 cents worth..

Pretty much what I was thinking, but always nice to see it come outta other peoples mouths

The option 2 idea.... I forgot to mention, i also have a biowheel power filter, so i was thinking i could get away with turning off the undergravel during the day, then back on at night, and not really have problems in the biological filter arena...
I was just wondering if the biological buddies in the gravel would be ok with circulation turned off during the day......

a strange idea, i know..

I think ill lean towards the powerhead idea....
Ill get everything working, then see how well the co2 is staying in solution.. then go from there..

 

[Lateral Line]

Unless very carefully done, powerheads will cause surface movement just as much as air uplift tubes and knock the CO2 out of solution. Biowheels are also notorious agitators and thus far from ideal for planted tanks.

If your tank is in balance, there is no need for airstones at night. My CO2 runs 24 hours and I've not used an airstone in a display tank for 15+ years.

I would expect a good amount of bacterial loss in the gravel bed if there is no flow for 12 hours or so, not a total wipe out, but certainly loss.

I guess if you are talking about adding CO2, you want a planted tank. That being the case, I'd strip out the ugf, and re-evaluate the rest of your equipment at the same time. I'd get a lowish turnover canister, run it in parallel with the ugf for a month to get it well populated, then do the knock down.