Disastrous first attempt, help me do better!

[Ecb]

My kids talked me into an aquarium a few months ago. We have never owned fish and did some research about how to keep the water stable and get the awuarium setup, but also relied a lot on the people in the fish department at Petsmart, which now I’m learning may not always be the best idea. We don’t have any good local mom and pop fish stores, so I’m not sure where else to go. Anyway, we bought a 36-gal tank with a heater and sponge filter, some artificial decor that the kids picked out, along with Quick Start and some test strips. We setup the water based on the quick start instructions and let it cycle for just over a week before adding fish (this was based on the Petsmart advice), I’m thinking this was too soon for fish now. We bought a few platies, a Molly and a Pleco (7 fish total) to start and everything was going great. We chose these fish because they were marketed as peaceful and easy for beginners. About 10 days later, we brought home 3 more platies and 2 days after that everyone started dying. Over the past 3 days, we have lost the entire tank of fish. Our temperature has been consistently at 76 degrees, test strips all show nothing by out of range and the water is clear. Some of the fish had a few white spots, so we started Ich treatment 2 days ago, but now that everyone is dead, I’m stopping that. When they first started showing signs of distress, I did a 30% water change and gravel vacuum. We want to try again, but with a better plan in place. I’m not sure what killed everyone, if the water wasn’t cycled enough or if it’s just that they came to us sick. It’s just so strange that everyone was doing so well until we added the newcomers. What do I need to do to get the tank in the best spot possible before adding fish again. Do I need to empty the tank and start over? What kind of startup plan do I need? There is so much information out there and I’m just overwhelmed and feeling frustrated that we could help those fish when they started to die.

 

[sharkweek178]

First step is learning about the nitrogen cycle. There's a comprehensive section here all about it. https://www.fishforums.net/threads/cycle-your-tank-a-complete-guide-for-beginners.475055/
It takes more than a week.

Next thing you want to do is find out your water hardness. You can find that on your water company website or look it up online by your zip code. Don't just rely on the terms "hard" or "soft". Get numbers. Because what's considered hard water for humans isn't necessarily so for fish. This helps you figure out what kinds of fish are best suited for your water. Now you can keep hard water fish in soft water and vice versa and they won't die immediately. But it's bad for their long term health and they won't be as happy as they could be.
The great thing is that you have lots of great options either way. Hard water fish include most livebearers (guppies, platies, mollies, swordtails), a lot of rainbowfish and African cichlids. Soft water fish include most tetras, rasbora, corydoras, bettas, gourami and South American cichlids.

 

[sharkweek178]

You kind of dodged a bullet with the pleco. Common plecos grow to 15-22 inches.

 

[Uberhoust]

In addition to @sharkweek178 comments and assuming you try again you might want to consider adding live plants to your tank. They provide cover for the fish and tend not to scratch or otherwise damage fish like some harder artificial plants do, and they can absorb some of the ammonia generated by the fish. I typically start with Vallisneria americana (aka Jungle Val) or Vallisneria spiralis (Spiral Val), both are easy to propagate and once started tend to grow easily. There are lots of other plants which will work equally good and perhaps better than vals, which people from this group can help you with. Good luck

 

[Lcc86]

Essentially now that your fish have passed, start from scratch and follow the advice about a fishless cycle. You'll never fully know the cause but it may be a bit of both an uncycled tank and potentially poorly fish.

Properly cycling will take about 6 weeks (approx) so turn it into a fun experience for your kids. A liquid test kit will be better to help you gauge where you're at with the cycle (API is a common brand if you can get their 6 in 1 liquid kit). Definitely agree with the live plants as these will generally be good for your water quality.

API also sell gH and kH tests for water hardness if you can't find it online for any reason. Once you know your water hardness you'll be able to look into fish that will suit while your tank cycles, again something you can get your kids to help with.

 

[CaptainBarnicles]

You've come to the right place, welcome aboard matey!

Rule number 1...take what the shop tells you with a pinch of salt, they want your money and will tell you what you want to hear so that you part with it.

Rule number 2...stick around and spend some time with us here, and we'll have you up and running a gorgeous aquarium for you and the family to enjoy

 

[sharkweek178]

In addition to @sharkweek178 comments and assuming you try again you might want to consider adding live plants to your tank. They provide cover for the fish and tend not to scratch or otherwise damage fish like some harder artificial plants do, and they can absorb some of the ammonia generated by the fish. I typically start with Vallisneria americana (aka Jungle Val) or Vallisneria spiralis (Spiral Val), both are easy to propagate and once started tend to grow easily. There are lots of other plants which will work equally good and perhaps better than vals, which people from this group can help you with. Good luck

When I started fishkeeping, live plants were so intimidating to me. Then I learned they really aren't. They are well worth it. And there are lost of easy plants out there. The vallisneria you mentioned. Java ferns, Anubias and Bucephalandras. Amazon swords. I really like cryptocorynes. And the various bacopas.
The learning curve is very forgiving and they are worth the effort.

 

[Oldspartan]

This a great place to learn. The forum has helped me a great deal plus it is a fun place if the bug bites you like it has me.