Plantnutx "F"AQ

I have been following Plantnutx for some time and will try to distill some of the useful knowledge into this FAQ. The names in brackets are the contributors of the answers. (Please let me know if you do not wish to be attributed or if you do not want your reply archived here at all.)


Types of Plants

 What are examples of low maintenance plants?
 (David Toh) … mention robust, and Anubias barterii comes to mind. Its not that 'choice' as exotics like echinodoruses or what, but it serves its purpose as a very hardy (i.e. difficult to kill) plant. Especially if u get the small leaved variety grown clustered, it provides some cover. For me, Cabomba is also low maintenance, despite being touted as a light demanding plant. But it might suffer bottom leaf senescence being a stem plant. So, that leaves things like sagittaria subulata for an easy ground cover and java moss for general decoration which provides good cover. I have been thinking of an all java moss design for some time! Oh, and hygrophila difformis (water wisteria) is very easy, but for some, not challenging enough hahaha


Plant problems

 What is causing my plants to have rotting leaves and stems at the bottom while they are healthy on top?
(Tze Ho Tan) I think the rotting is due to too dense planting and light not reaching the lower levels. Will plant more sparsely next time.
(Beverly Wladyka ) I have also heard that plants can rot from not having enough water circulation around them. Poor circulation means CO2 and other nutrients are not reaching the leaves and the plant eventually rots and dies.


Types of Equipment

 What is tempered glass? Is it harder to scratch than ordinary glass?
(Mark Pan) Tempered glass is simply glass that has been, well, tempered :)
It is tougher, but no less prone to scratches than other glass. The thing is, it is bloody difficult to scratch glass! I use steel wool, for instance to clean the insides of my tank, with absolutely no scratches. And I reckon mine is one of those el-cheapo tanks. If I'm not wrong, virtually all tanks 4 feet plus in size are made of tempered glass. Just imagine if one of these glass tanks breaks!


Equipment Problems

 I am using an Eheim 2228 canister filter. Is it wise to inject CO2 directly into one of the inlets (t-junctioned) to the filter? I am trying to save up buying a reactor/diffuser. Sow-Yan
No problem doing that....although you mind find that if there are too many co2 bubbles inside the canister filter...you might get decavitation at the impeller area...that causes that irritating whirring noise...as the impeller tries to push the bubbles out. If this happens too often, it might cause the impeller to break a blade... rgds, roy

U 'll most likely kill the bacteria in your filter if U do that. Not advisable. martin

Hi Martin Why would the bacteria in the canister filter get killed by co2 injection directly into the canister.?? Care to explain this theory ?? I had thought that if you just injected the co2 elsewhere in the tank, wouldn't your canister filter have the same Ph level/co2 levels as in the main tank? Also, the optimal levels of o2 and co2 are independent of each other, and thus, I doubt that by injecting co2 directly into the canister would cause a O2 deficiency to an extend that it will actually kill all your aerobic/nitrifying bacteria. rgds, roy

Roy, The proportion of water in the canister compared to the whole tank makes a big diff. By injecting co2 in a wide open tank distributes the co2 as it diffuses into the whole tank, say 80% water. If the initial output of co2 was directly injected to a canister, say 20% water compared to the whole tank, co2 will always be more concentrated within the canister. I can't prove that it will certainly kill the bacteria but with bacteria in the canister also produces co2, it kind of gets really risky. martin

Hi Roy, actually I only advice CO2 injection to the cannister if it is large enough. For Sow Yan case of 2228, that's is okay but must be careful not to create a big bubble nest in it. As what you have mentioned, it will cause some noises as well. Kind of make me worry when it rattles ... For a small filter like those internal types, I have experience a breakdown in the system when I do that. The filter could not dissolve the bubble fast enough and cause a big bubble nest in the filter elements. That's a concentration of CO2 unlike the dissolved one in the water. That portion of the bubble will not be contact with O2 rich water for quite a long period. Dunno, just my theory. But at 4 bubbles per seconds, I still prefer a diffuser of any type. Right Roy ? Sow Yan, a Taiwan made spiral glass coil diffuser is so far one of the cheapest, effective mean and as nice looking as the original "very costly" type- S$14 at Clementi. Not too sure anywhere else got it. Kenn

Hi Kenn Actually....on my eheim 2226 that is connected to a OFA surface skimmer.... it's turned to pull at maximum rate from the surface and every now and then, bubbles get drawn into the canister and a few seconds later...gets spewed out from the outlet with a zillion tiny bubbles....so far, it's running 1 1/2 yrs like that and the impeller/motor is still okay. I think this fine for the eheim canister filters, but I've heard that fluvals may not stand up to this sort of treatment. Well...for small internal filters, probably might happen....but how are you going to bubble your co2 into the internal filter....they do not have inlet tubes....unless you drill a hole into the filter body....Well...in my 1 ft cube tank, I have the tiny Eden brand internal filter and my dupla diffusor is directly below the filter....see some fine bubbles get drawn into the internal filter....so far no problems. But how did you get that huge co2 bubble into the internal filter anyway?? I would assume that at least some surface of the co2 bubble would be in constant contact with some part of the water flow and any co2 left would have dissolved long before it causes that area to be anaerobic. I still doubt if that would have caused the bacteria to die there....unless that portion of the sponge filter had turned 'black' and stinks of H2S. But all said...best alternative is to use a reactor or diffusor......4 bubbles/second... reactor for sure, unless you like seeing millions of co2 bubbles being blown all over the tank.... rgds, roy

Hello Roy, Kenn, Martin and Plantnutx people, Thank you very much for your kind help. You really enlightened me up on the best place to inject CO2. I will look up the glassy spiral diffusor at Clementi. Hey, I think I saw one at Petmart's display tank. Also, I may consider building a simple one using PVC pipes. Please refer to this webpage for construction details: http://www.thekrib.com/Plants/CO2/reactor.html Best wishes, Sow-Yan


FAN ASSISTED COOLING
Just a question, I know some of members here use a small fan to cool their tanks, just wondering at what temperature were the tank when using a small fan. So far I have tried one fan, and it managed to cool from 30 to 28. If I use more fans will it cool further? Thanks, Philip
To add on to the query, how are the resultant evaporation rates? Is it high enough to require constant refilling of water within one week? Philip, where did u get your fan? at what price? regards David

Hi Philip, With a small DC fan on a my 3ft tank, temp goes from 31/32C down to 27/28C... very effective! Now I can even grow Java moss in my tank. Evaporation, though, is very high. Have to top up water every 3 days. Fan is ON only when lights ON - 10hrs a day.

Hi folks In my tanks with fans: one with fan on for 24 hrs achieves a drop in water level of about 1 cm per day; the other tank with the fan on during lights on (about 12 hrs)... evaporates a bit lesser. But of these tanks are in my balcony, which gets pretty hot in the afternoons... maybe that's why I see so much evaporation. As for fans...if you go for DC Computer type fans... it's available between $8-10 at Sim Lim, for AC fans...it's a bit more expensive (and heavier)...between $20-$22 for those 4" type.. rgds, roy

That's not true! If you want to buy fans, why don't you check out the big electronic store at Rochor Center, second floor. I bought mine [AC Fan???] for 10 plus only...That's the truth -check it out! edwyn

Hi all I got my AC fan pretty cheap at 14.8 at Sim Lim tower third floor, comes with cable. DC I saw there was less than 10 each I think, u have to check out the price though. Regards Philip

Well Phillip, i don't think it will make a difference whether its 1 or 10 fans :-) Fans can only pull temp down to a certain degree, after which they are no longer effective. The parameters which affect the fan's performance are:
1) The ambient temperature. In my house, it's less than 30 degrees, that is, between 28-29 degrees on most days.
2) The prevailing humidity. Fans work on the principle of evaporation. (You know, the can of beer wrapped in a wet towel thing) If the air in your house is saturated with water (high humidity), then the fans would have little or no effect. This can happen to houses which are very poorly ventilated, and have leaky rood problems (don't laugh, many HDB have leaky roof problems without the owners even realising it)
3) The size of the fan. The fan must generate substantial air movement. Something which the tiny 2" and 3" ones are incapable of. I use a 4-inch diameter fan, which blows hard enough (vertically) on the water to cause it to ripple. This brings my temps down to an average of 26 degrees. On cold days, it goes down to 24 sometimes. I leave the fan running for 24-hours a day, for maximum evaporation.
So the number of fans really doesn't make a difference here. I know one person who has rigged up about 4 smaller fans in a housing. It doesn't bring his tank's temps down to the same levels are mine, simply because his house is more humid and hotter than mine :-) I believe also, its because he's using the smaller fans, which have less power to move air in an open space (like the space between fan and water) Hope this helps. Mark P

 

Addresses of LFS

 Where is Aquatechnic?
Aquatechnic Pte Ltd
7 Kampong Kayu Rd
Singapore 438162
Tel (+65) 348 0048
Fax (+65) 348 1735
Website: http://nasia.com/aquatechnic
Email: aqua7@post1.com
Aquatechnic is the Singapore agent for Dupla and Teco (chillers)
They also manufacture high-end glass tanks.

Where is Aquamart?
705 Sims Drive #01-12A
Shun Li Industrial Complex
Singapore 387384
Tel (+65) 741 2022
Fax (+65) 744 2322
Email: aquamedicsea@usa.net