OP, you're in a very frustrating place.
You're so close to some good ideas, but stubbornly sticking to several wrong-headed or even ignorant positions that will lead, long-term, to disappointment with your tank.
To address your very first question: Yes, it absolutely is possible to do a 20g reef tank for under $450. Mine cost about $850 to put together overall (or would have cost that much, if I were putting it all together new from the store). In reality, mine was much cheaper than that because I re-used equipment I already had. I'm in a very different place from you, though, and I spent on fancier equipment that you do not need to get a reef going.
Petco tank vs IM tank ($200 cost-savings), Amazon black-box lights over my Kessils ($260 cost savings) and a Jebao powerhead instead of my AI Nero ($100 cost savings), and you've already saved enough to cover the addition of a HOB power filter and still come in under your $450 budget.
Having said that:
1) Absolutely do not use saran wrap to cover your tank. It'll work as a temporary measure, but long-term it'll cause you far more trouble than it's worth. Either use a polycarbonate or glass lid (not recommended) or a screen top lid (recommended). You can get a relatively cheap DIY kit for your tank off of BRS for about $30. Go that route and don't look back.
2) You need to dial back your expectations as to what you can do in a 20g tank. Macroalgae, softies, and 2-4 small fish? Totally doable. But the kind of fish you're looking at are mostly unsuitable for that kind of tank.
I know you are hung up on the Clarkii clownfish, but it really gets too big and is too aggressive for a 20g tank. If you don't like Ocellaris or Percula clowns (and I get where you're coming from - it took me years to get over my Nemo hate), then any of the skunk clowns will give you a more peaceful fish that's better suited to a 20g.
Midas blenny, Valentini puffer, lion fish, mandarin, hawkfish - I get it, they're really cool fish. But they all need a much bigger tank to really be happy. Micropredators in particular are a heartbreak waiting to happen. They are all very difficult to train onto commercial foods, and all of them will VERY quickly exhaust your tank's ability to produce food for them. You can externally cultivate food for them, but that adds complication and expense to your build, and I would not try to do that with a limited budget as part of my first saltwater experience.
The thing with fish is that it is not just about how big they get. It's also about:
A 20 gallon tank is VERY small for most saltwater fish. Some of them can tolerate it, but most of them can't. Clowns, damsels, some gobies, some dottybacks, some blennies, some wrasse, and some basslets. Any of the major predatory fish just aren't going to feel comfortable in that tank, and they'll manifest it by attacking their tank mates and engaging in aberrant behavior. Micropredators like mandarins are out as well; a small tank simply doesn't have the real estate to sustain a copepod population large enough to support a mandarin.
With a tank that size, you need to pick ONE idea and stick with it, and have all of your decisions built around that ONE idea. So, you want to have a lagoon-type tank with softies and macroalgae? Cool. That's doable in a 20 gallon. So you need to research what each of those organisms that you want to keep needs to thrive, and determine whether you can provide that in your tank and with the amount of maintenance you are willing to commit to. That might include dosing, skimmer, filtering, feeding heavy, harvesting macroalgae, fragging back corals, or any number of other activities.
Instead of simply declaring what you are going to do and showing off 'tanks that you like,' and declaring that you can do such-and-such because your buddy says you can do it, tell us what you would like to do, ask for help in how to do it, and recognize that in a 20 gallon tank, you cannot have everything you want and you are going to have to make some compromises.
There's a lot of experience in this forum, and we're more than happy to help you achieve your goals. But we're also looking out for the long-term experience of you and your eventual fish, and some things simply won't work. You wouldn't put an elephant in a one-bedroom third-floor apartment, but for a lot of the fish you've been asking about, you're basically asking us to help you do just that.
You're so close to some good ideas, but stubbornly sticking to several wrong-headed or even ignorant positions that will lead, long-term, to disappointment with your tank.
To address your very first question: Yes, it absolutely is possible to do a 20g reef tank for under $450. Mine cost about $850 to put together overall (or would have cost that much, if I were putting it all together new from the store). In reality, mine was much cheaper than that because I re-used equipment I already had. I'm in a very different place from you, though, and I spent on fancier equipment that you do not need to get a reef going.
Petco tank vs IM tank ($200 cost-savings), Amazon black-box lights over my Kessils ($260 cost savings) and a Jebao powerhead instead of my AI Nero ($100 cost savings), and you've already saved enough to cover the addition of a HOB power filter and still come in under your $450 budget.
Having said that:
1) Absolutely do not use saran wrap to cover your tank. It'll work as a temporary measure, but long-term it'll cause you far more trouble than it's worth. Either use a polycarbonate or glass lid (not recommended) or a screen top lid (recommended). You can get a relatively cheap DIY kit for your tank off of BRS for about $30. Go that route and don't look back.
2) You need to dial back your expectations as to what you can do in a 20g tank. Macroalgae, softies, and 2-4 small fish? Totally doable. But the kind of fish you're looking at are mostly unsuitable for that kind of tank.
I know you are hung up on the Clarkii clownfish, but it really gets too big and is too aggressive for a 20g tank. If you don't like Ocellaris or Percula clowns (and I get where you're coming from - it took me years to get over my Nemo hate), then any of the skunk clowns will give you a more peaceful fish that's better suited to a 20g.
Midas blenny, Valentini puffer, lion fish, mandarin, hawkfish - I get it, they're really cool fish. But they all need a much bigger tank to really be happy. Micropredators in particular are a heartbreak waiting to happen. They are all very difficult to train onto commercial foods, and all of them will VERY quickly exhaust your tank's ability to produce food for them. You can externally cultivate food for them, but that adds complication and expense to your build, and I would not try to do that with a limited budget as part of my first saltwater experience.
The thing with fish is that it is not just about how big they get. It's also about:
- Their temperament
- The amount of waste they produce
- How active they are
- What environment they need
- How they interact with tank mates
A 20 gallon tank is VERY small for most saltwater fish. Some of them can tolerate it, but most of them can't. Clowns, damsels, some gobies, some dottybacks, some blennies, some wrasse, and some basslets. Any of the major predatory fish just aren't going to feel comfortable in that tank, and they'll manifest it by attacking their tank mates and engaging in aberrant behavior. Micropredators like mandarins are out as well; a small tank simply doesn't have the real estate to sustain a copepod population large enough to support a mandarin.
With a tank that size, you need to pick ONE idea and stick with it, and have all of your decisions built around that ONE idea. So, you want to have a lagoon-type tank with softies and macroalgae? Cool. That's doable in a 20 gallon. So you need to research what each of those organisms that you want to keep needs to thrive, and determine whether you can provide that in your tank and with the amount of maintenance you are willing to commit to. That might include dosing, skimmer, filtering, feeding heavy, harvesting macroalgae, fragging back corals, or any number of other activities.
Instead of simply declaring what you are going to do and showing off 'tanks that you like,' and declaring that you can do such-and-such because your buddy says you can do it, tell us what you would like to do, ask for help in how to do it, and recognize that in a 20 gallon tank, you cannot have everything you want and you are going to have to make some compromises.
There's a lot of experience in this forum, and we're more than happy to help you achieve your goals. But we're also looking out for the long-term experience of you and your eventual fish, and some things simply won't work. You wouldn't put an elephant in a one-bedroom third-floor apartment, but for a lot of the fish you've been asking about, you're basically asking us to help you do just that.
