Science project

[roka64]

My soon-to-be stepdaughter hase to do a project. I am planning on the cycle of a new SW tank ("freshies", you are more than welcome to have some input). We will have pics and everything. I need a good hypotheses. For you that don't remember (like me), here are the steps:
Steps of the scientific method
1. Name the problem or question
2. Form an educated guess (hypothesis)
of the cause of the problem and make
predictions based upon the hypothesis
3. Test your hypothesis by doing an experiment or study (with proper controls)
4. Check and interpret your results
5. Report your results to the scientific
community
Any and all suggestion would be great! Plus, we will have pics and might be able to add it to a sticky, for future folks.

PS. We are doing a fishless cycle, and don't want to subject any live animals to "heck", if you knoe what I mean...

 

[krap101]

you could set up 2 tanks with pretty much the same stuff in them. you could try to set up 2 tanks with 2 different temps, maybe 70 and 80? and see which one cycles first? thats easy enough

 

[Blazeherd2306]

you could set up 2 tanks with pretty much the same stuff in them. you could try to set up 2 tanks with 2 different temps, maybe 70 and 80? and see which one cycles first? thats easy enough

Good idea.

The question could be something like:

How does the water temperature in a saltwater aquarium affect the rate in which bacteria grows?

And you could have three tanks to test it with. One would be the constant (80 degree water), another would be at 65 degrees, and another at 95 degrees.

The only problem with this is that you would have to buy a chiller, unless you want to keep the room at 65 degrees.

 

[QTOFFER]

What grade is your stepdaughter in, roka64? Does she have the 4 - 6 weeks that will be neccessary for a cycle to occur?

I think it would be neat to test the cycling efficiency of the various products out there, as opposed to plain old ammonia. Instead of tanks, I don't see why you couldn't use well rinsed 1 gallon milk containers.

Something like this comes to mind:
Tank 1: ammonia
Tank 2: ammonia + gravel or filter material from established tank
Tank 3: ammonia + Marineland BioSpira
Tank 4: ammonia + Hagen Cycle
etc

 

[roka64]

[quote"QTOFFER"]What grade is your stepdaughter in, roka64? Does she have the 4 - 6 weeks that will be neccessary for a cycle to occur?[/quote]

She is 14 and in all honor classes. Yes, it is due in December.

The project is for a science fair, so you know, the BIG cardboard with explanations and picture.

Thanks for the advice and keep it coming!

 

[Jchillin]

Since the problem has been identified, I'll just go with the graphics you should display. A nice illustration of the nitrogen cycle will do wonders IMO.

PS - Yeah, I did that.

 

[roka64]

Jchillin
Since the problem has been identified, I'll just go with the graphics you should display. A nice illustration of the nitrogen cycle will do wonders IMO.

That was what I was thinking. Now what kindof hypothese would you all suggest?

PS I wanted to test your advice on the quote, as well. Ok, just tried it.....mental note, leave out the =....! Ack, took it out and still don't get it....

Thanks again!

 

[roka64]

I think I will go with two tank sizes. Hypothese:
Two tanks of different sizes should take the same time to cycle.
I will use a 100/125G vs. a 20 and match them as closely as possible. Does this sound like a good idea? Plus I will have two more tanks! LOL!

 

[krap101]

maybe a plant with ferts/co2 and just ammonia (for nitrates)

i read something about different plants (if healthy) can kill other plants. they put out some chemical and you cant keep certain kinds of plants together. i know one was anacheris and i forgot all the other ones.. don't know how reliable that'll be though

 

[roka64]

krap101, your first post, gave me the idea for two tanks. I was thinking the two tanks, sand and the fishless cycle (SW) with a raw cocktail shrimp. I will scale the smaller tank so it mirrors what's in the larger....or I could go with an even smaller tank, for a more drastic effect....hmmm (maybe a bigger tank).
What do you all think?

 

[fish 'n' fries]

The only catch I could see would be that it may be difficult to control for all the factors other than just size (although if she needs to address confounding factors...that would be easy). You'd probably have different amounts of substrate etc. You may have better luck with having the temperature be the variable. Of course then you'd need to end up with two new tanks the same size.

Another thought might be hypothesis "the addition of living material speeds the development of bacteria" using plants instead of fish (I've never had saltwater...so correct me if that wouldn't be feasible.) You could then have two tanks, one with plants the other without.

Good luck. It sounds like a fun project!

 

[krap101]

I dunno if this would be considered as cruel, but i was thinking this as a bio project last year. Yall know about the canals and the lateral line. You could try using a sonic toothbrush, and try catching a fish, then do it without the toothbrush. either they wont be able to feel you catch them... ot they'd go crazy... heh

i dont think i have the site i had a couple years ago, it had a list of the plants that hurt other plants through chemicals. this site has the name wrong but gives you the general idea. its called alleopathy
http://fins.actwin.com/fish/aquatic-plants/month.9707/msg00322.html

this ones slightly better (didnt read all of it)

http://scarab.msu.montana.edu/agnotes/docs/228.htm

heres an experiment with a eucalyptus tree and grass seedings
http://www.usc.edu/CSSF/History/2002/Projects/J1610.pdf

guess its really called allelopathy

http://en.wikipedia.org/wiki/Allelopathy

the tank idea is still fine, but i think this might be easier to control variables and stuff. because in the tanks, you cant accurately tell when exactly the cycle is completely done.

 

[roka64]

I agree, the variables would be there, but if I scaled the two tanks equally, it should work. I kind of like the idea of "the addition of living material speeds the development of bacteria", but I would need an ammonia source in both tanks, to start the cycle. My thought is really, to show that the nitrification cycle is/should be the same in a large as in a smaller tank....If that makes sense.

 

[newfound77951]

If the two tanks have the same filtration rate, same ratio of substrate to volume, and are of the same general shape, then you'll limit confounding factors. I wouldn't try it with a 20H and a 125, for example, because the surface area to volume is just too different, and the surface area to volume of the glass, substrate etc would also be really different. Although that in itself would be a neat idea; to get two tanks of the same volume but different shapes, and see if there was any difference in how fast the tank cycled. For example a 20L and 20H, or a hexagon vs rectangular tank. Oh, the possibilities!

 

[roka64]

I wouldn't try it with a 20H and a 125, for example, because the surface area to volume is just too different, and the surface area to volume of the glass, substrate etc would also be really different.

I'm thinking, this would prove a point. I don't believe the size of the tank matter in cycle time. If both are scaled as closely (remember, this is for an 8th science project, so we won't be using the clean room for this) as possible (I know there will be some variables, but we can limit them some) we should be able to prove that size doesn't matter....right?

 

[newfound77951]

Not sure I totally understand, but here's my thought....if you did the experiment with two different sized and differently shaped tanks, and got no difference in cycle time, then you're OK. BUt, if you get different results, then you won't be able to tell if the differences were from size alone or from some other factor. I know from doing other experiments that "bottle effects" can make a huge difference in the outcome of an experiment, ie the size of the bottle can affect the results, and a lot of the time it's because in a small bottle, there is just more glass area per water volume for bacteria and other things to settle on.

Just my 2 cents....this is a middle school science project, and I'm more used to dealing with PhD stuff, so i might be a little too picky. Whatever was you do it, I think it will be fun and your stepdaughter will learn a lot!

 

[fish 'n' fries]

I'm with newfound77951 that if there is a difference you won't be able to tell...but I'm also in the same situation of thinking of more formal experiments.

For a lot of upper level experiments, however, you need to explain what may have affected your results. If she needs to do that, she could easily say that the tanks weren't perfectly scaled.

If they're the same general shape and you have proportionate amounts of substrate (whatever percent of the area etc.) and the same gph of filtration...you're probably right...for an 8th grade project...I think it'd be great!

 

[roka64]

Hey thanks! You all, as usual, have given awesome advice! I was kind of thinking that I could show the cycle times are about the same in two extremely different sized tanks. I was also thinking it might help some new folks, down the line, that a 20G/125G, no matter the size, the cycle will be roughly the same. Of course, we won't get into the whole cycle with uncured/cured LR or "seeding" the tank, LOL!

 

[krap101]

imo it would be more interesting (more contrast) if you seeded one tank with something, and left the other one without it, and recorded the time inbetween the two tanks. you could try making it a little bit different by seeding the bigger tank and they might think the smaller one will still cycle faster?

also, how will you scale ammonia? same amount or proportional?

 

[Finatic]

How about going simple, three small tanks, one empty (water of course), one with sand, one with LR and same amount of sand. Then try to cycle them.

Could make an argument about cycling and SA for the bacteria to grow.

Or what would be cool is if you could figure some way to stop the Nitrobacter from growing and keep the NO2 peaking with no NO3 production, vs a tank that can go through the full cycle. Could make the argument that you need two different sets of bacteria for the complete cycle.

Maybe I'm thinking too simple, but I am also trying to think cheap. Using 125 gal worth of LR is $$$$.