Soft Water

Question
I have a 10 gallon tank with these fish in it.

1   Otocinclus Cat
1   Cat Fish (Bottom Feeder)
1   Ghost Shrimp
5   Baby Sword Tails
2   Zebra Danios
1   Cardinal Tetras
2   Blue gromi's

The tank has been going for almost 3 months now.
PH is around 8.2 and temp is about 79 degrees.
Ammonia and nitrite levels are good.  Everything else in the tank is good.
My question is can you use soft water in the tank.  Someone told me you can but he works at a huge superstore.  I do use aquarium salt in the tank but not sure if you should always add salt when you do a water change.  I have had a hard time keeping fish alive.  The last 6 fish I bought died.  I just bought 2 blue gromi's today and have my fingers crossed.

Wendy  

Answer
Hi Wendy;

Don't worry about the pH. As your tanks ages it will naturally drop on it's own. PH is only dangerous for your fish if it fluctuates. The fish are used to what the pH is now and changing it will cause them stress and possibly kill them. The pH recommendations on fish profiles are only what the fish are usually living in when in the wild. The fish we get now are raised in captivity in concrete breeding ponds. The pH is much different than their wild ancestors. Captive bred fish breed and thrive in these conditions so you don't need to worry about it. If you have any shells or coral in the tank you should take it out. It will cause the pH to continue to rise as long as it stays in there. They are a skeleton of a dead creature that will always give off minerals. Limestone does this too.

Unless the fish are sick you don't need to add salt. It is a good thing to keep on hand just in case though. It helps kill parasites and helps the fish with stress.

Your tank is overcrowded so if the gouramis don't make it, it would be best not to replace them. The maximum safe population for a 10 gallon tank is 10 total inches of adult fish. The fish you have now are going to grow so it will only get worse. I think that's why any extras have died. It's just too much for the tank. Here is the projected size of them;

Otocinclus - 2"
Catfish - 1 to 12 inches depending on the type. It's  probably a cory cat. They get about 1 to 2 inches depending on the variety.
Ghost Shrimp - 1"
Swordtails - 3" to 5"
Zebra Danio - 2"
Cardinal Tetra - 1"
Blue Gouramis - Dwarf 3.5" or opaline, threespot, twospot all get 4.5"

Just in case you've been misinformed; It is a myth that bottom feeders and other scavengers don't count in the population. They still create waste of their own and impact the system too. Maybe not as much, but they still "count".

The way to help keep your existing fish alive is to faithfully make water changes of 25% once a week. Vacuum the gravel every two weeks and don't overfeed. Be sure the fish totally consume all food from all areas of the tank within 5 minutes. Any leftovers, even if eventually eaten, simply created un-needed excess waste that becomes dangerous.

Followups Welcome

At Your Service;
Chris Robbins

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