Hi,
I just bought an used 45gallon bowfront tank with fishes (mostly mollies and platies).
It is a nice upgrade over my 20gallon.
I moved to Oakville (Ontario,CA) and I see that here the water hardness is very high.
API strip tests tell me that the general hardness (GH) is 180ppm or 10 dGH(highest possible measure in the strip) and the Carbonate Hardness (Kh) is between 80 and 120ppm or 4.5-6.7dKH.

I want to change the fishesfor 6 Redline Sharks, 8 White clouds and 3 panda cory (or otos), I have arround 2 year of experience but I dont know how important the water hardness is how it affect the fishes.

I dont want to buy the new ones until I know what to do in this situation, what do you think?

Carlos

Howdy, Carlos.

I'm on a well with very hard water myself (GH varies from 500-680, KH between 180-300). Speaking from my own experience with the above species, I have a nice school of eight roseline sharks in a 55 gallon tank, and I had a group of white clouds for several years, until they died of old age. Both these species should do well; just make sure you acclimate them to the tank slowly, using a drip if possible.

I've had decent luck with otos. My experience has always been that if ya can get by the first month then they'll survive. IME they really need a well established tank, so I recommend ya wait until ya have a bit of an algae film before adding them.

All in all I've had poor luck with cories in my water. Of course, it is quite a bit harder than yours. I'm not going to say definitely ya should or shouldn't. Fish that have been tank-bred for generations usually do well in a fairly wide range of water parameters, and I believe panda cories are tank bred now for the hobby. Just make sure to acclimate them slowly if you do try. Regardless, I'd really recommend a group of at least six. Cories are schooling fish and will be more active in groups. Adding 3 or 4 more to your stock list will not increase the bioload on your tank enough to worry about.

Make sure your new tank is cycled prior to adding fish. Ya can speed the cycle up significantly by using some of the substrate from your old tank and/or some of the filter medium.

Welcome to FWM! glad to have ya here and hope this helped.

Ivan

Ivan, Thanks a lot for your answer.
I'm very exited about this tank, it is already well cycled, nitrites=0ppm and 19 fishes there.

i just have a question, when you say "...just make sure you acclimate them to the tank slowly, using a drip if possible."

What does that mean?, the fishes are either in my tank or in the lfs, so I'm confused on how can I acclimate them slowly to the tank.

I already found a lfs that will receive my current fishes so I'm almost there! :-)

thanks again for your comment!

Carlos

Okay, sorry I didn't get back to you sooner, it was a busy weekend.

When floating fish, the best way is to gradually replace a portion of the water in the bag with water from the tank. After 30 minutes or so when temperatires have equalized, take a quarter cup of water from the tank and pour it in the bag, then pour out a like amount. Do this every 10 to 15 minutes over the course of an hour or so. If there is a big difference between the parameters in your tank and the water the fish are in, ya can draw it out longer by doing smaller changes at a time.

With a drip, you put the fish in a small container and gradually set a drip with air line tubing dripping into the container, at 2-4 drops per second. The bigger the difference your parameters are from the water the fish are in the slower the drip. Anyways every 10-15 minutes remove as much water as has been added by the drip. Let this go for a coupla hours. I would reccommend this if your parameters are vastly different from those in the bag the fish are in and for more delicate species.

WYite