Merging two 20gs into a 40g? Advice, please. :)

[totalnoob]

**Edit: After remeasuring the piece I want to put the tank on, it is one inch too thin for a 40 standard and 2 inches too short for a 40 long..Talk about crap! Would this same scenario work for a 35-38g?**

Good evening, everyone! Just as the title says, I am looking to merge my two 20g tanks into a single 35-38g?. I have been poking around to do some research, and I think I have a pretty decent handle on everything I am supposed to do, but I would still like some solid advice to help me.

I currently have two 20g tanks, both have been up and running about 7 months now. I would like to merge them into a single 35-38g? community tank. The 20g long currently houses 8 zebra/leopard danios, 7 neon tetras, and two nerite snails. My 20g high has 6 harlequin rasboras, 5 corydoras julii, and 2 otos.

My questions are as follows:
- Would the tank be overstocked with my existing fish? AQ Advisor says it would only be 57% stocked, but I know it's not the most reliable.
- AQ Advisor also said that not all fish are temperature compatible - is this true, or is there a happy medium I can achieve in regards to temp?
- If this IS manageable, I would like to put the 40g where my 20g long currently sits - what is the best way to go about doing that without stressing the fish too much?
- I currently run a Fluval Aquaclear 30 on my 20 long and an Aquaclear 20 on my 20 high. Can I use both filters on the 35-38g?, or would I have to upgrade to an Aquaclear 50? (I love the Aquaclear filters, so I plan on continuing to use them).
- If I *do* have to upgrade the filter, I assume I would still have to use the two existing filters to seed the new one?
- What size heater would I need, and what is the best way to make sure that I don't get cold spots? (I currently use a long bubble rod in my 20 long, it works nicely, the tank is evenly heated - so I assume I can do this in a 35-38g??)
- Given that my fish are generally community fish, are there any special considerations I need to take when merging them?

And I guess, generally, is there any other advice I need, or other things I need to be aware of?

Thanks in advance, sorry for so many questions!

 

[TMRC Exotics]

I see no reason why the stock is incompatible. All should go nicely with room to add.

Yes you can use both filters. After the tank is cycled I would look into using a single bigger filter that can hold the media from your previous filters to avoid a mini cycle.

I can't remember the necessary heater wattage but it should be on the packages. Good filter flow should achieve adequate heating, no air stone should be necessary.

 

[totalnoob]

Thank you for your reply! I just re-measured the surface I wanted to place the tank on and as it turns out, it is literally one inch too thin (17" deep instead of 18" CURSES!!!!).........AHHHHHHHH!!!

Would the same setup work for a, say, 35 or 38 gallon tank? Ugh, I am so mad...ONE INCH!! (And it's a lovely piece of furniture we have nowhere else to put it in our house so the tank *has* to go on it, there's nowhere for a standalone).

I am so upset, I swore it was the right size. GRRRRRRR!

 

[t4runnr]

You could always get a 3/4" thick plywood cut to size and place that on top of your stand.

 

[totalnoob]

I could, but it's a very nice piece of furniture in a really visible room of the house, lol. I'm not sure how my husband would feel about it, but I could run it by him! XD

 

[t4runnr]

Paint or stain it to match. Or even put some custom wood trim. It would be cheaper than getting a new stand and you can get the tank that you really want.

 

[totalnoob]

Paint or stain it to match. Or even put some custom wood trim. It would be cheaper than getting a new stand and you can get the tank that you really want.

I actually found a 38g today at a LFS, and it is the correct dimensions and would fit nicely, so I think that's a nice compromise. As long as not having the two extra gallons isn't going to impede the bio load of my tank overall, that is.

 

[TMRC Exotics]

The two gallons will not, the footprint could.

 

[totalnoob]

The two gallons will not, the footprint could.

So I don't fully understand the tank footprint thing. I know it has to do with the dimensions of the tank, but I don't understand how it affects the bio load? Is it a ppm thing or a volume or surface area thing, or?

I do not plan on stocking any more fish than those I currently have in the tank. Mostly I am just attempting to merge the two tanks to a) free up some horizontal space in my house and b) make less work for myself as far as tank maintenance goes. I have (too many according to my husband) a lot of tanks, of mostly bettas, and I spend a lot of time maintaining them and the fish they house. I enjoy it, but it does get tiring, and I think for simplicity's sake, just having one community tank is best. I am happy with the fish I have, though, and do not wish to get more.

I also don't plan on adding a lot of decorations, probably just what I have plus maybe a few more silk plants and maybe a piece of mopani, but that would be it. I don't do well with planted tanks (read: I am too lazy for co2 and ferts, so generally I just have marimo or java fern cuz they're set and forget for the most part), so I don't plan on having a complicated set up.

With those factors in mind, will going down to 38 from 40 affect my plan? I was not hell bent on a 40, and am fine with a 38, as long as my fish will thrive and be fine with it too.

 

[TMRC Exotics]

The footprint just refers to its length and width. Not all tanks are created equal, take a 20 gallon. The 20 long is 30" long x 12 wide. A 20 high is only 24" long by 12 wide. The difference is the height, and height isn't as important as lateral swimming space. The 38 should be fine as long as the footprint still allows plenty of room.

 

[totalnoob]

Gotcha. The 38 is 36 1/4" long, and I believe the 40 is also 36" long. The issue for me was more width front to back, as my stand is only 17" across (where a 40 is 18" wide). My stand is 46 inches long and a 40 long is 48 inches, lol.

But length wise, both the 38 and 40 are the same. So I believe it will be okay.

 

[t4runnr]

One other suggestion is to nail/screw/adhere a 1" thick strip of wood at the back of the stand where the top of the strip is flush with table top. Since its at the back, it won't be very visible. Then you can maximize the foot print of the tank. 18" deep tanks are really nice. I like that depth on my 75 gal. Just so much more room to place things in like driftwood, plants (live or fake) and any other ornaments.

 

[Brookster123]

One other suggestion is to nail/screw/adhere a 1" thick strip of wood at the back of the stand where the top of the strip is flush with table top. Since its at the back, it won't be very visible. Then you can maximize the foot print of the tank. 18" deep tanks are really nice. I like that depth on my 75 gal. Just so much more room to place things in like driftwood, plants (live or fake) and any other ornaments.

That's what I'd do.. a 40 breeder is an excellent footprint..

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