Hi,

I would like to get your thought on water movement in a planted tank, what you did with your tank and the result.

There are two school on water movement, fast circulation with 2x-3x tank capacity/hour and slow circulation with 1x-1.5x tank capacity/hour.

Fast circulation is thought to provide good circulation of nutrient and CO2 to the plants and remove any build up of waste material from the surface of plant leaves. This might be true in a large tank as the CO2 reactor is usually located at one corner of the tank and may not circulate well if there are pockets of stagnant water. You can see this from the direction of O2 bubbling.

Fast circulation can be achieve by using a large filter or smaller filter with an additional powerhead to circulate the water. Using large filter with too much water circulation can reduce the effectiveness of bio filteration. We can reduce this by using filter with controllable flow but this is contrary to the purpose of using large filter to create good circulation.

One method to increase water movement is the placement of filter return. Place it low near the bottom of tank will create strong current and good for plants that like strong current such as cryptocoryne but might uproot stem plants especially after pruning and replanting. Placing the return nearer to the top of the tank will create strong water movement at the top but may cause debris to accumulate on the gravel and less water movement for dwarf plants.

So, we need a strong water movement and good biological filteration. This probably can be achieve by using slow filtration with powerhead or large filter with a section of the filter blocked to slow down a portion of the water getting thru the filter similar to Dennerle's filtration system.

Okay, so what is your preference and what have you implemented in your planted tank?

Hi. interesting post. My thoughts and experience (others may not agree LOL). I used to be quite anal about water flow. Added powerheads and messed with different flow rates. The result, algae still flourished. Now, this is how I run my tank.

1. Water flow is just moderate - fish food swirls slightly but not a whirlpool.
2. Water column doesn't turn into a tsunami
3. Put the diffuser near the outflow to push the CO2 bubbles around so that it has more time for the water to absorb the CO2
4. Focus on a more efficient way of diffusing CO2
5. Focus more on plant growth - ferts, lighting, pruning
6. Cleaning filter an a more frequent interval
7. Dosing ferts when plants are awake and not asleep
8. Clearing debris during water change

So, without worrying so much on water flow and not using powerheads, the results is much better for me. Plus, using ADA soil and ferts allowed me to get a head start in better plant growth, and enjoy a planted tank that is free from algae. Only occasionally algae pops up, but much more under control. Hope this helps.

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Steven

Slow water movement...as slow as possible.
if the tank is a matured one, no worries about debris or algae. it doesnt matter if the difuser is at the corner of a big tank... co2 will get to the plants. just because you cant see this happening with naked eyes doesnt mean its not happening.

Hands up ...if any of you guys actually find any sucess in using fast flowing waters.

btw creeps ..on your point 7 about dosing ferts when plants are awake, remember i once mention fert dosage only goes in during daylight hours and got plenty of objections from the sifus..one even went as far as saying dosage only at lights out..hehehe...seems you are catching up on the game huh. well, an old man's word will not carry any weight unless one tries out for themselves. hahaha

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Ari, yeah I did try and got better results. Besides, it's something easy to experiment with. Won't lose any money one. Hahaha.

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The nose runs and the feet smell - go figure
Steven

haha...are you still having problem with algae?..since you had trust me once , would you like to trust me again?....if you do ...try this.

all the talk or advice or what you have read about lower PH will discourage algae..we read this everywhere from the internet to labels on algae remover, but doesn it carry any weight? well, this is a long argument and im one of the few who believes the oppsite.

with PH value of 7.5, my tanks are free from algae. the hardness is set at 8dKH. note...at 8dKH plants like nuphars, cobomba and ferns will not do well, so you must increase the KH slowly, best at 1dKH a day. For rotalas, ludwigias, and other red plants they will be at their best.
but the most important thing is how well your bacterias are growing? always mix around, dont rely on only one kind of bacteria. i use 3 kind of PSB and 1 bio bacteria.

if one had always followed the rule of book and yet problems still presist , then its time to do the oppsite...if you trust me at all , that is.

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Wah Ari like taikor talking hehehe. Not much algae problems these days. However, would your method work on a smaller tank? If yes, then I can test with one spare tank that I have.

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The nose runs and the feet smell - go figure
Steven

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small tank ah...aiyo i neber try planting in small tank before, minimum is 4ft. actually the bigger the tank , the more easier to control water para.
for small tank is problem to get all the right lighting to fit in, and the temp bounce like rubber ball...well, you can try lar...see how, then i learn from you lar.

what i know is ...people tends to go overboard with small tanks...a 2footer is getting the same amount of ferts and co2 as a 4footer. with less plants in a 2 footer, of course algae is going to have a upper hand...so...you plan yourself lar the amount of ferts and co2 needed. better less than being over.

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Everyone Has a Photographic Memory..........some just dont have film!