New to fish, New tank, unique problems?

Hi,
I recently purchased a house. In the house was a 150 gallon tank which the previous owners had filled with water, some gravel, and a few tiny plastic plants. No fish. They did not want to move it and asked if I would like to keep it. I said I would love to. My only previous tank was a tiny little thing with a single goldfish for my barracks in Korea - which I only kept for a few months until I moved back to the states. I had no idea how large this tank was...
I have not yet fully read through the Nitrogen cycle. It will by my next thing to do now that I have heard of it. I have a few issues first, though.
First, I had the tank running for several months while I was getting moved in with nothing in it (except the colored gravel and like five tiny plastic plants). I conditioned it with some conditioner the previous owners had in the lower cabinet. After a few months, I noticed that algae was starting to grow, so I bought a water test kit (liquid, not paper). I tested my water prior to having any fish in the tank. All numbers looked good, so I figured it was okay to go and purchase some algae eaters and let them do their job on the tank.
After researching on the net, I bought a few Hillstream Loaches, a few mono shrimp, three nerrite snails, a few cherry shrimp, and an otocinclus. No big deal, just something to scrub the greenery away so that I could buy fish the next weekend.
They did their job, the slight bit of algae that I had was gone by the next day, and I got a little concerned that they wouldn't have enough to eat so I went and bought a few algae balls so they would be able to eat before I got other fish in here.
By day three, I could see almost no fish in my tank. Every here and there I could see my loaches cruising and all three snails, but nothing else. I couldn't figure out what was going on, except that these fish were tiny. Much smaller than I expected, and I started thinking that maybe my filter ate them. The next day I decided to clean my "socks" (I have three, and it is weird for me to use this terminology like I know what I am talking about, because I don't), and I found my otocinclus, multiple shrimp, I have no idea what ever happened to the cherry shrimp because they were so small that they looked like fingernail clippings.
So, I thought that I had just started out so terribly small that I never should have had fish and shrimp in this tank that were that small. No one local had larger fish, so I ordered three bristlenose plecos online. One was DOA, one didn't look good (barely swimming) and that proved to be correct as he died within a day, the third is still swimming and doing what pleco's do.
I went to the local fish store and started looking at the largest freshwater stuff they had, which turned out to be five angel's, a cute little rainbow shark, and four bettas (large is relative here, they are still very small, but much bigger than the others I had bought). I brought them home and they loved their new digs. Day 2, every female betta was nowhere to be found, day 3 the male betta disappeared from the tank. The angel's and rainbow have been living it up in their ultra-roomy new home until I came home tonight. One of my filters had one of the angels (the largest) sucked into it partially, and he was clearly dead. I had to put gloves on and peel him out of the filter slot. I went to change my socks and found all four bettas in the socks when I changed them so they definitely went down the filtration.
So, finally, to my question (I apologize for the long rambling backstory). I looked at the pump, and I cannot see a nameplate or anything on it, so I have no idea what kind of pump it is. I don't know if it is running to hard (as I said, the last owners never even used the tank, they just had it pumping). I can tell you that I have four hoses that return water to the tank, and the stream coming off of each seem to be pretty strong - strong enough that it will tumble unaware fish when they enter the stream. I have no idea if this is normal for a pump to eat your fish and shrimp. In fact, I currently have several shrimp living in one of my lower (overflow?) tanks because I don't want to put them back in the upper tank and have them die on the way back down (I discovered them down there and left them there when I was changing socks).
I am not sure what to do. I don't want to keep killing fish. I don't want to spend money just to make minced fish. I have tested my water, and it still remains looking good on all levels. The fish that haven't been sucked down into oblivion are healthy, swimmy, doing what fish do - to include the orginal loaches and snails. I am worried that if I buy more fish and continue to fill the tank with awesome fish, that I will just become a fish serial killer and wallet assassin.
Any suggestions? Also, when I was looking on the pump for a nameplate, I didn't see anything to adjust the flow. I might have missed it, but it wasn't obvious if I did.
Thanks for any help you can provide.

 

Is there any way to put intake sponges on the intakes? Might be called prefilters.

 

I am too new to this to know that these are. I will have to look them up, but it seems that I have a set of vertical vents close to the bottom and a set of vertical vents on the top (the water level for the top is about halfway up the vents). I would also be a bit concerned with choking the supply (rather than reducing the outflow) as that would likely stress the motor causing by making it suck harder for the same output and cause other problems - to include premature pump failure, overheating, etc.
But I will take a look at this, thank you for the suggestion.

 

If its like a grate what about mesh? Like plastic canvas. I was thinking the intakes were a tube.

 

Is your 150 gallon a 4ft or 6ft tank ?

Also, Do you have a sump, in which a smaller tank is below the main tank?

If so, that's actually very good. Sumps offer excellent filtration . You will just need to find fish that will not be sucked into the strainers/weirs.

A 150 gallon with a sump would be a good setup for some Geophagus and some Severums.

Geophagus Red Head Tapajos reach 5"-6" and are peaceful while WinemillerI reach up to 8". A group of 5-7 Geophagus would be great.

Severums would work well with Geophagus. They reach up to 8" fully grown and 2 or 3 of the following would look great in your 150g: Gold Severum, Red Shoulder Severum, Turquoise Severum and/or Red Spotted Severum.

 

So you have a SERIOUS problem with the fish you're putting into the tank. They are NOT compatible. Ask some questions here regarding stock, we can help you.

I guarantee you have fish killing each other and you're finding them dead, stuck on the filter, after the fact.

First, stop buying fish! You can't just put any fish with any fish, it doesn't work like that. Bettas can NOT be put together. You WILL get people here who will argue they have had sororities that worked, but that's few and far between with only the PERFECT fish, and even then it can go bad at any minute. Also, you really don't want Angels or Bettas with Rainbow sharks, they are semi-aggressive, territorial and WILL kill them.

You need to know if the tank is cycled first and foremost. Buy the API Master Test Kit and check ammonia, nitrite and nitrates. If you have ammonia or nitrites, you aren't cycled. If you have nitrates with no ammonia or nitrites, you are probably cycled...., but to what bioload we don't know.

So my advice:

1: No more fish
2: Buy test kit
3: Stock tank accordingly
4: Post pics of your set up so we can help with that

 

Agreed with above. Definitely don't buy anymore fish until you are sure your tank is cycled. In the meantime try and find something to cover the intake pumps. It sounds like you have a sump, which is awesome. A 150 gallon with a sump should provide a lot of stocking options. Once you are sure your tank is cycled, take some time and research a stocking combination you will like. It will be more enjoyable for you and fish that are compatible together will be happier as well.

Also what do you mean by "cleaning socks" just out of curiosity?

 

So you have a SERIOUS problem with the fish you're putting into the tank. They are NOT compatible. Ask some questions here regarding stock, we can help you.

I guarantee you have fish killing each other and you're finding them dead, stuck on the filter, after the fact.

First, stop buying fish! You can't just put any fish with any fish, it doesn't work like that. Bettas can NOT be put together. You WILL get people here who will argue they have had sororities that worked, but that's few and far between with only the PERFECT fish, and even then it can go bad at any minute. Also, you really don't want Angels or Bettas with Rainbow sharks, they are semi-aggressive, territorial and WILL kill them.

You need to know if the tank is cycled first and foremost. Buy the API Master Test Kit and check ammonia, nitrite and nitrates. If you have ammonia or nitrites, you aren't cycled. If you have nitrates with no ammonia or nitrites, you are probably cycled...., but to what bioload we don't know.

So my advice:

1: No more fish
2: Buy test kit
3: Stock tank accordingly
4: Post pics of your set up so we can help with that

HI Duane,
I appreciate your candid feedback, and truly thank your real and actual admonition of my actions. As I already stated, I HAVE stopped buying fish (your #1) and have stated that I came to some online forums to understand what I don't understand. I am a very straightforward guy, and I appreciate the same. I like someone that can immediately tell me what I am doing wrong, so that I stop doing that wrong. So, since you were highly candid, let me answer you...
I had no idea that any fish in my tank was killing another. I was very clear that I didn't want any aggressive fish when I spoke with any of my fish "experts." If this didn't happen, I promise you it wasn't my fault, I attempted to keep aggressive fish out of my tank - or I would have just went and bought an Oscar or similar and threw smaller fish in there for his food supply. I was told that every fish in the tank (subtracting the rainbow shark) was massively passive and I didn't need to worry about them. I was further told that even my rainbow shark was only mildly aggressive, but in a tank as big as 150 gallons, it would not be an issue - unless overcrowding became an issue which it isn't because, as I stated, I only have had a few fish in this massive tank at all - EVER.

I would also like to state that you clearly didn't actually read my post, you just read what you wanted to read. You stated on #2, buy a test kit. I CLEARLY stated that I bought a test kit (Liquid, not paper) and tested my water and all results were excellent. I later stated that I tested it once more, with that kit, prior to joining this forum and posting this question. It remained well within tolerances. If you can tell me how to do that better, please do. I would greatly appreciate it.

Your #3 is actaully one of the things that I joined this forum for. I would love to figure out how to properly stock this 150 gallon tank, I tried on my own, didn't go so good, my post was asking for help. I am glad that you understood that ask! I appreciate you being here. Most posts online are talking about tanks unbelievably smaller than this tank... 5 gallons? 10 gallons? 25 gallons? The largest I found was 3 x smaller than my tank, which I have no idea how to take care of.

It is currently very late, and I am going to go to bed. However, I will absolutely post pictures of this aquarium tomorrow. This aquarium is larger than I ever thought I would see in my life, deal with in my life, have in my house ever. It might not be the same for you, and I can only say that I am super jealous of you, because this is your life...

 

do you have a picture? Normally you can fit sponge over almost anything but there should be a way to turn it down. You are having problems with your fish getting sucked up and also fish dying that is probably because your tank is not cycled. Do not get anymore fish until you have completed your cycle then slowly add fish. You can have a lot of fun with a 150!
edit: I typed this right after you posted your question but it didn't post for some reason.

 

I would also try to rehome any fish that are left and check if the tank has been cycled...

I've read from your initial post that you let the tank running for a few months with just the gravel and plastic plants?
If so, if I'm not mistaken, there was no source of ammonia for any beneficial bacteria to start feeding on.
That could also be the reason why your tests come out clean.. If there's no source of ammonia, both nitrite and nitrate will also be 0.
If there are fish in the tank, test the water a few times a day to see what happens. If the ammonia builds up without any sign of nitrite, your tank has not been cycled and you need to do that urgently.
If there is 0 ammonia, 0 nitrite and some nitrate, you're all set and you can ignore the above

Like others mentioned, it might be wise to stop buying fish and research individual species, especially how they behave together.
Angels and bettas aren't a good match. Also, if you want a betta, put only a single male in the tank on its own or with a few females but don't put two male bettas. They will fight...
The red tailed shark is also semI aggressive and territorial, just like the angels. Might also not be a good fit.

Some ideas I can give you:
Pleco and corydoras for the bottom with maybe a few snails and shrimps.
Angelfish are fine and they will love such a big tank. Try to have some plants in there with large narrow leaves. They love to swim through those.
Have a look at gouramis. They are nice fish and can live with the angels but you also have to be careful with stocking of the gouramis. They need to be in pairs and a single mail. The mails are not as aggressive as the betta. They usually work if the school is big enough and the tank is big enough.

A school of tetras is always a good addition to the tank, just as guppies, mollys and other live bearers.

There's plenty of cool stuff you can put in such a tank so if you see a fish you like, research and ask.

What I love to do is to go to my local store and look at the fish. If there's a fish I like, I note the name and research it. It usually starts by asking about them in the local store. I ask about their water condition, their behavior and how large they get + how they behave together with other fish I like/have in the tank.

 

When you get you’re tank fully cycled and ready for fish I suggest:
1 bn pleco
20-100 corries or several groups of different types
If you want a unique stock do
5 male pearl gouramis and 15-20 females.
and you could also do another schooling fish

 

I'm just gonna add my 2 cents I had a 210 gallon tank with 4 oscars To black tiger 2 albino 1 catfish huge one plecostomus huge But they all didn't start out that way had that tank going for years. By far was my favorite set up ever. Unfortunately The tank sprung a leak. Have not replaced it yet sent my fish to a rescue. Now all I have is a 60 gallon. Little back story on me. Been in the hobby over 25 Years. It sums like to me you have slots in multiple areas for your overflow There is nothing wrong with having fish in your tank while you cycle it it is called a fish in cycle. You just have to keep up on your water quality tests in water changes until the cycle happens. You can either buy big fish that are completely compatible that won't get sucked up or you can buy some kind of mesh to put over the slots so you can have a ton of little guys however you want to stock your tank there is a way to fix every problem. I wouldn't want to be a fish murder either. I cycled a 20 gallon tank with 20 fish in it before it is possible not that hard. With a tank the size you have it all depends on how much extra time you have. Also the saying goes The bigger the better the easier to maintain and that is 100% true.....

 

It sounds like the tank was originally setup for saltwater, which requires a strong flow from your return pump. A sump (the part under the tank) does allow for great filtration, and I agree with Islandvic on the ultimate eventual stocking suggestions. Keep testing your water. If you have angelfish (even one) living in there then you have a fish-in cycle. If you have angelfish and shrimp and snails all living in there then you're probably well on your way to being cycled, if not done already. There is the "add all the ammonia and wait until it's all processed" method, and there is also the "add 2 fish in 150 gallons of water and just go real slow" method. Either will work with a little common sense and an abundance of vigilance.
A word of caution regarding placing screens, mesh, sponges, or anything over the weir (that's the slotted part of the wall ((the overflow)) that drains into the sump). Keep a close eye if you choose to do that. If your return pump is pumping water out of the sump back into the tank faster than whatever is blocking the overflow will let it through...you could have a flood on your hands. Even if the clean mesh lets plenty through, things collect on that prefilter and slow your flow down.
Also watch the level of water in the sump itself. One of the nice things about a sump is it keeps the water level constant in your display. So any evaporation that takes place will lower the water level in the sump. If it gets low enough you can suck air into the return pump and then you have bubbles shooting out of the return nozzles.
My first course of action in your shoes would be to see if there is a dial or a valve or something on the return pump where you can slow it down. If you slow the return flow to the tank that will in turn slow the rate of water going through the overflow. ALso make sure that someone didn't block the lower slots in the overflow wall. Sometimes saltwater keepers will do that to increase surface skimming.
If that doesn't work, then try some mesh or very very coarse prefilter sponge over the weir. Just keep an eye on the level of the water for a few miutes.
And don't freak out or let anyone else freak you out. You don't need our permission for any of this, and I for one am glad to see you here and asking the right informed questions. I hate seeing a big gorgeous tank go to waste!

Also if you like the shark...rainbow sharks do fine with angels IME. Angels and Geophagus should be fine together as well.

 

Adding my 2 cents again.
If it were me I would just spend the money on getting fish that are already a decent size. With a tank like that you can see them from a mile away.

I miss my big tank with my oscars They used to play with ping pong balls and let me pet them...

 

I am too new to this to know that these are. I will have to look them up, but it seems that I have a set of vertical vents close to the bottom and a set of vertical vents on the top (the water level for the top is about halfway up the vents). I would also be a bit concerned with choking the supply (rather than reducing the outflow) as that would likely stress the motor causing by making it suck harder for the same output and cause other problems - to include premature pump failure, overheating, etc.
But I will take a look at this, thank you for the suggestion.

In a sump system (vs. a Hang on the back filter) the pump isn't "sucking" water from the tank. The pump pushes water from the sump TO the tank, until it reaches the overflow wier, where gravity takes over and sends the water back to the sump. You can fill the center chamber of your sump with foam, bioballs, or whatever combination of filter media you choose... The water level getting too low in the sump only hurts the pump when it gets low enough that it's pulling air.