Using External Canister with Rain Bar

[alantan9]

Hi People,

i have just changed from OHF to an external filter with rainbar attached. But my question is how come with the rain bar i cant actually see any obvious water movement in the tank? I have checked that my external filter is working fine by raising the rain bar above water level and water is coming out. Please enlighten me. Thanks a lot...hehehehe....


cheers,
Alan

[eddyq]

Hi Alan,
My guess is the filter's flow rate is slow/small filter? or aim the rain bar toward the surface to see some movement.

[michael lai]

Hi alan,
Did you check if there is any chokage?

[ranmasatome]

your filter may not be powerful enough.. there is some physics involved.. its just water pressure difference when its comeing out from one hole as opposed to a few along a bar...it gets weaker along the bar.. the first one being the strongest..

[vinz]

The main reason is that the waterflow is now distributed to many small holes, instead of one big current concentrated in one area.

It may seem deceptively less water movement then one big current, but what you have now is many small currents distributed across the tank. In effect, water circulation may be vastly improved although not obvious.

Also, what is the flow rate of your new filter? If it is significantly lower then your old OHF, the water flow will be less.

What is the size of your tank? What filter (brand and model) did you buy? What media did you put inside and in order?

[alantan9]

hi vinz and all,

the flow rate is 1100 l / hr but i am using a 2ft rain bar to spread out the flow cos if its coming out from the outlet, its like water rushing out and the current is quite strong. Btw, the model is SPACE ADV (the auntie said its italian brand). Actually when i on the lights i can see the fine particles being blown towards the front of the tank as i position my rain bar such tat it is blowing towards me in front of the tank. Thanks


cheers,
Alan

[vinz]

Well, IMO, that flow rate is good for a 200 to 400 litre planted tank. Just position the rainbar for better circulation and CO2 distribution (if you are injecting CO2).

In my experience, putting the rainbar closer to the bottom of the tank, across the length of the backwall and pointing forward is one of the best arrangements.

[evolim83]

One other reason might be the height of your tank!
Though unlikely, but I hope you are not placing your cannister too low or too far away from your tank!
Check your tubings too!
Make sure there are no nips and the excess length should be removed!
Cos 1100l/hr sounds fine to me!

[alantan9]

okie dokie...thanks a lot for ur advise....=)